Table 1 of Sec.   1037.106--CO2 Standards for Class 7 and Class 8 Tractors by Model Year
                                                  [g/ton-mile]
----------------------------------------------------------------------------------------------------------------
                                      Phase 1         Phase 1         Phase 2         Phase 2         Phase 2
                                   standards for   standards for   standards for   standards for   standards for
         Subcategory \1\            model years     model years     model years     model years     model year
                                     2014-2016       2017-2020       2021-2023       2024-2026    2027 and later
----------------------------------------------------------------------------------------------------------------
Class 7 Low-Roof (all cab                    107             104           105.5            99.8            96.2
 styles)........................
Class 7 Mid-Roof (all cab                    119             115           113.2           107.1           103.4
 styles)........................
Class 7 High-Roof (all cab                   124             120           113.5           106.6           100.0
 styles)........................
Class 8 Low-Roof Day Cab........              81              80            80.5            76.2            73.4
Class 8 Low-Roof Sleeper Cab....              68              66            72.3            68.0            64.1
Class 8 Mid-Roof Day Cab........              88              86            85.4            80.9            78.0
Class 8 Mid-Roof Sleeper Cab....              76              73            78.0            73.5            69.6
Class 8 High-Roof Day Cab.......              92              89            85.6            80.4            75.7
Class 8 High-Roof Sleeper Cab...              75              72            75.7            70.7            64.3
Heavy-Haul Tractors.............  ..............  ..............            52.4            50.2            48.3
----------------------------------------------------------------------------------------------------------------
\1\ Sub-category terms are defined in Sec.   1037.801.

    (c) No CH4 or N2O standards apply under this
section. See 40 CFR part 1036 for CH4 or N2O
standards that apply to engines used in these vehicles.
    (d) You may generate or use emission credits for averaging,
banking, and trading as described in subpart H of this part. This
requires that you calculate a credit quantity if you specify a Family
Emission Limit (FEL) that is different than the standard specified in
this section for a given pollutant. The FEL may not be less than the
result of emission modeling from Sec.  1037.520. These FELs serve as
the emission standards for the specific vehicle subfamily instead of
the standards specified in paragraph (a) of this section.
    (e) The exhaust emission standards of this section apply for the
full useful life, expressed in service miles or calendar years,
whichever comes first. The following useful life values apply for the
standards of this section:
    (1) 185,000 miles or 10 years, whichever comes first, for vehicles
at or below 33,000 pounds GVWR.
    (2) 435,000 miles or 10 years, whichever comes first, for vehicles
above 33,000 pounds GVWR.
    (f) You may optionally certify Class 7 tractors to Class 8
standards as follows:
    (1) You may optionally certify 4x2 tractors with heavy heavy-duty
engines to the standards and useful life for Class 8 tractors, with no
restriction on generating or using emission credits within the Class 8
averaging set.
    (2) You may optionally certify Class 7 tractors not covered by
paragraph (f)(1) of this section to the standards and useful life for
Class 8 tractors. Credit provisions apply as follows:
    (i) If you certify all your Class 7 tractors to Class 8 standards,
you may use these Heavy HDV credits without restriction.
    (ii) This paragraph (f)(2)(ii) applies if you certify some Class 7
tractors to Class 8 standards under this paragraph (f)(2) but not all
of them. If you include Class 7 tractors in a subfamily of Class 8
tractors with an FEL below the standard, exclude the production volume
of Class 7 tractors from the credit calculation. Conversely, if you
include Class 7 tractors in a subfamily of Class 8 tractors with an FEL
above the standard, you must include the production volume of Class 7
tractors in the credit calculation.
    (g) Diesel auxiliary power units installed on tractors subject to
standards under this section must meet PM standards as follows:
    (1) For model years 2021 through 2023, the APU engine must be
certified under 40 CFR part 1039 with a deteriorated emission level for
PM at or below 0.15 g/kW-hr.
    (2) Starting in model year 2024, auxiliary power units installed on
tractors subject to standards under this section must be certified to
the PM emission standard specified in 40 CFR 1039.699. Selling,
offering for sale, or introducing or delivering into commerce in the
United States or importing into the United States a new tractor subject
to this standard is a violation of 40 CFR 1068.101(a)(1) unless the
auxiliary power unit has a valid certificate of conformity and the
required label showing that it meets the PM standard of this paragraph
(g)(2).
    (3) See Sec.  1037.660(e) for requirements that apply for diesel
APUs in model year 2020 and earlier tractors.

Sec.  1037.107  Emission standards for trailers.

    The exhaust emission standards specified in this section apply to
trailers based on the effect of trailer designs on the performance of
the trailer in conjunction with a tractor; this accounts for the effect
of the trailer on the tractor's exhaust emissions, even though trailers
themselves have no exhaust emissions.
    (a) Standards apply for trailers based on modeling and testing as
described in subpart F of this part, as follows:
    (1) Different levels of stringency apply for box vans depending on
features that may affect aerodynamic performance. You may optionally
meet less stringent standards for different trailer types, which we
characterize as follows:
    (i) For trailers 35 feet or longer, you may designate as ``non-aero
box vans'' those box vans that have a rear lift gate or rear hinged
ramp, and at least one of the following side features: Side lift gate,
side-mounted pull-out platform, steps for side-door access, a drop-deck
design, or belly boxes that occupy at least half the length of both
sides of the trailer between the centerline of the landing gear and the
leading edge of the

front wheels. For trailers less than 35 feet long, you may designate as
``non-aero box vans'' any refrigerated box vans with at least one of
the side features identified for longer trailers.
    (ii) You may designate as ``partial-aero box vans'' those box vans
that have at least one of the side features identified in paragraph
(a)(1)(i) of this section. Long box vans may also qualify as partial-
aero box vans if they have a rear lift gate or rear hinged ramp. Note
that this paragraph (a)(1)(ii) does not apply for box vans designated
as ``non-aero box vans'' under paragraph (a)(1)(i) of this section.
    (iii) ``Full-aero box vans'' are box vans that are not designated
as non-aero box vans or partial-aero box vans under this paragraph
(a)(1).
    (2) CO2 standards apply for full-aero box vans as
specified in the following table:

                    Table 1 of Sec.   1037.107--Phase 2 CO2 Standards for Full-Aero Box Vans
                                                  [g/ton-mile]
----------------------------------------------------------------------------------------------------------------
                                                              Dry van                    Refrigerated van
                   Model year                    ---------------------------------------------------------------
                                                       Short           Long            Short           Long
----------------------------------------------------------------------------------------------------------------
2018-2020.......................................           125.4            81.3           129.1            83.0
2021-2023.......................................           123.7            78.9           127.5            80.6
2024-2026.......................................           120.9            77.2           124.7            78.9
2027+...........................................           118.8            75.7           122.7            77.4
----------------------------------------------------------------------------------------------------------------

    (3) CO2 standards apply for partial-aero box vans as
specified in the following table:

                   Table 2 of Sec.   1037.107--Phase 2 CO2 Standards for Partial-Aero Box Vans
                                                  [g/ton-mile]
----------------------------------------------------------------------------------------------------------------
                                                              Dry van                    Refrigerated van
                   Model year                    ---------------------------------------------------------------
                                                       Short           Long            Short           Long
----------------------------------------------------------------------------------------------------------------
2018-2020.......................................           125.4            81.3           129.1            83.0
2021+...........................................           123.7            80.6           127.5            82.3
----------------------------------------------------------------------------------------------------------------

    (4) Non-box trailers and non-aero box vans must meet standards as
follows:
    (i) Trailers must use automatic tire inflation systems or tire
pressure monitoring systems with wheels on all axles.
    (ii) Non-box trailers must use tires with a TRRL at or below 5.1
kg/tonne. Through model year 2020, non-box trailers may instead use
tires with a TRRL at or below 6.0 kg/tonne.
    (iii) Non-aero box vans must use tires with a TRRL at or below 4.7
kg/tonne. Through model year 2020, non-aero box vans may instead use
tires with a TRRL at or below 5.1 kg/tonne.
    (5) Starting in model year 2027, you may generate or use emission
credits for averaging to demonstrate compliance with the standards
specified in paragraph (a)(2) of this section as described in subpart H
of this part. This requires that you specify a Family Emission Limit
(FEL) for CO2 for each vehicle subfamily. The FEL may not be
less than the result of the emission calculation in Sec.  1037.515. The
FEL may not be greater than the appropriate standard for model year
2018 trailers. These FELs serve as the emission standards for the
specific vehicle subfamily instead of the standards specified in
paragraph (a) of this section. You may not use averaging for non-box
trailers, partial-aero box vans, or non-aero box vans that meet
standards under paragraph (a)(3) or (a)(4) of this section, and you may
not use emission credits for banking or trading for any trailers.
    (6) The provisions of Sec.  1037.241 specify how to comply with the
standards of this section.
    (b) No CH4, N2O, or HFC standards apply under
this section.
    (c) The emission standards of this section apply for a useful life
of 10 years.

Sec.  1037.115  Other requirements.

    Vehicles required to meet the emission standards of this part must
meet the following additional requirements, except as noted elsewhere
in this part:
    (a) Adjustable parameters. Vehicles that have adjustable parameters
must meet all the requirements of this part for any adjustment in the
physically adjustable range. We may require that you set adjustable
parameters to any specification within the adjustable range during any
testing. See 40 CFR 86.094-22 for information related to determining
whether or not an operating parameter is considered adjustable. You
must ensure safe vehicle operation throughout the physically adjustable
range of each adjustable parameter, including consideration of
production tolerances. Note that adjustable roof fairings and trailer
rear fairings are deemed not to be adjustable parameters.
    (b) Prohibited controls. You may not design your vehicles with
emission control devices, systems, or elements of design that cause or
contribute to an unreasonable risk to public health, welfare, or safety
while operating. For example, this would apply if the vehicle emits a
noxious or toxic substance it would otherwise not emit that contributes
to such an unreasonable risk.
    (c) [Reserved]
    (d) Defeat devices. 40 CFR 1068.101 prohibits the use of defeat
devices.
    (e) Air conditioning leakage. Loss of refrigerant from your air
conditioning systems may not exceed a total leakage rate of 11.0 grams
per year or a percent leakage rate of 1.50 percent per year, whichever
is greater. This applies for all refrigerants. Calculate the total
leakage rate in g/year as specified in 40 CFR 86.1867-12(a). Calculate
the percent leakage rate as: [total leakage rate (g/yr)] / [total
refrigerant capacity (g)] x 100. Round your percent leakage rate to the

nearest one-hundredth of a percent. This paragraph (e) does not apply
for refrigeration units on trailers; similarly, this paragraph (e) does
not apply for self-contained air conditioning or refrigeration units on
vocational vehicles even if they draw electrical power from engines
used to propel the vehicles. For purposes of this requirement,
``refrigerant capacity'' is the total mass of refrigerant recommended
by the vehicle manufacturer as representing a full charge. Where full
charge is specified as a pressure, use good engineering judgment to
convert the pressure and system volume to a mass. If air conditioning
systems with capacity above 3000 grams of refrigerant are designed such
that a compliance demonstration under 40 CFR 86.1867-12(a) is
impossible or impractical, you may ask to use alternative means to
demonstrate that your air conditioning system achieves an equivalent
level of control.

Sec.  1037.120  Emission-related warranty requirements.

    (a) General requirements. You must warrant to the ultimate
purchaser and each subsequent purchaser that the new vehicle, including
all parts of its emission control system, meets two conditions:
    (1) It is designed, built, and equipped so it conforms at the time
of sale to the ultimate purchaser with the requirements of this part.
    (2) It is free from defects in materials and workmanship that cause
the vehicle to fail to conform to the requirements of this part during
the applicable warranty period.
    (b) Warranty period. (1) Your emission-related warranty must be
valid for at least:
    (i) 5 years or 50,000 miles for Light HDV.
    (ii) 5 years or 100,000 miles for Medium HDV (except tires).
    (iii) 5 years for trailers (except tires).
    (iv) 1 year for tires installed on trailers, and 2 years or 24,000
miles for all other tires.
    (2) You may offer an emission-related warranty more generous than
we require. The emission-related warranty for the vehicle may not be
shorter than any basic mechanical warranty you provide to that owner
without charge for the vehicle. Similarly, the emission-related
warranty for any component may not be shorter than any warranty you
provide to that owner without charge for that component. This means
that your warranty for a given vehicle may not treat emission-related
and nonemission-related defects differently for any component. The
warranty period begins when the vehicle is placed into service.
    (c) Components covered. The emission-related warranty covers tires,
automatic tire inflation systems, tire pressure monitoring systems,
vehicle speed limiters, idle-reduction systems, hybrid system
components, and devices added to the vehicle to improve aerodynamic
performance (not including standard components such as hoods or mirrors
even if they have been optimized for aerodynamics), to the extent such
emission-related components are included in your application for
certification. The emission-related warranty also covers other added
emission-related components to the extent they are included in your
application for certification. The emission-related warranty covers all
components whose failure would increase a vehicle's emissions of air
conditioning refrigerants (for vehicles subject to air conditioning
leakage standards), and it covers all components whose failure would
increase a vehicle's evaporative emissions (for vehicles subject to
evaporative emission standards). The emission-related warranty covers
these components even if another company produces the component. Your
emission-related warranty does not need to cover components whose
failure would not increase a vehicle's emissions of any regulated
pollutant.
    (d) Limited applicability. You may deny warranty claims under this
section if the operator caused the problem through improper maintenance
or use, as described in 40 CFR 1068.115. For example, it may be
appropriate to require the seals on automatic tire inflation systems to
be replaced during the warranty period.
    (e) Owners manual. Describe in the owners manual the emission-
related warranty provisions from this section that apply to the
vehicle.

Sec.  1037.125  Maintenance instructions and allowable maintenance.

    Give the ultimate purchaser of each new vehicle written
instructions for properly maintaining and using the vehicle, including
the emission control system. The maintenance instructions also apply to
service accumulation on any of your emission-data vehicles. See
paragraph (i) of this section for requirements related to tire
replacement.
    (a) Critical emission-related maintenance. Critical emission-
related maintenance includes any adjustment, cleaning, repair, or
replacement of critical emission-related components. This may also
include additional emission-related maintenance that you determine is
critical if we approve it in advance. You may schedule critical
emission-related maintenance on these components if you demonstrate
that the maintenance is reasonably likely to be done at the recommended
intervals on in-use vehicles. We will accept scheduled maintenance as
reasonably likely to occur if you satisfy any of the following
conditions:
    (1) You present data showing that, if a lack of maintenance
increases emissions, it also unacceptably degrades the vehicle's
performance.
    (2) You present survey data showing that at least 80 percent of
vehicles in the field get the maintenance you specify at the
recommended intervals.
    (3) You provide the maintenance free of charge and clearly say so
in your maintenance instructions.
    (4) You otherwise show us that the maintenance is reasonably likely
to be done at the recommended intervals.
    (b) Recommended additional maintenance. You may recommend any
additional amount of maintenance on the components listed in paragraph
(a) of this section, as long as you state clearly that these
maintenance steps are not necessary to keep the emission-related
warranty valid. If operators do the maintenance specified in paragraph
(a) of this section, but not the recommended additional maintenance,
this does not allow you to disqualify those vehicles from in-use
testing or deny a warranty claim. Do not take these maintenance steps
during service accumulation on your emission-data vehicles.
    (c) Special maintenance. You may specify more frequent maintenance
to address problems related to special situations, such as atypical
vehicle operation. You must clearly state that this additional
maintenance is associated with the special situation you are
addressing. We may disapprove your maintenance instructions if we
determine that you have specified special maintenance steps to address
vehicle operation that is not atypical, or that the maintenance is
unlikely to occur in use. If we determine that certain maintenance
items do not qualify as special maintenance under this paragraph (c),
you may identify this as recommended additional maintenance under
paragraph (b) of this section.
    (d) Noncritical emission-related maintenance. Subject to the
provisions of this paragraph (d), you may schedule any amount of
emission-related inspection or maintenance that is not covered by
paragraph (a) of this section

(that is, maintenance that is neither explicitly identified as critical
emission-related maintenance, nor that we approve as critical emission-
related maintenance). Noncritical emission-related maintenance
generally includes maintenance on the components we specify in 40 CFR
part 1068, Appendix I, that is not covered in paragraph (a) of this
section. You must state in the owners manual that these steps are not
necessary to keep the emission-related warranty valid. If operators
fail to do this maintenance, this does not allow you to disqualify
those vehicles from in-use testing or deny a warranty claim. Do not
take these inspection or maintenance steps during service accumulation
on your emission-data vehicles.
    (e) Maintenance that is not emission-related. For maintenance
unrelated to emission controls, you may schedule any amount of
inspection or maintenance. You may also take these inspection or
maintenance steps during service accumulation on your emission-data
vehicles, as long as they are reasonable and technologically necessary.
You may perform this nonemission-related maintenance on emission-data
vehicles at the least frequent intervals that you recommend to the
ultimate purchaser (but not the intervals recommended for severe
service).
    (f) Source of parts and repairs. State clearly in your written
maintenance instructions that a repair shop or person of the owner's
choosing may maintain, replace, or repair emission control devices and
systems. Your instructions may not require components or service
identified by brand, trade, or corporate name. Also, do not directly or
indirectly condition your warranty on a requirement that the vehicle be
serviced by your franchised dealers or any other service establishments
with which you have a commercial relationship. You may disregard the
requirements in this paragraph (f) if you do one of two things:
    (1) Provide a component or service without charge under the
purchase agreement.
    (2) Get us to waive this prohibition in the public's interest by
convincing us the vehicle will work properly only with the identified
component or service.
    (g) [Reserved]
    (h) Owners manual. Explain the owner's responsibility for proper
maintenance in the owners manual.
    (i) Tire maintenance and replacement. Include instructions that
will enable the owner to replace tires so that the vehicle conforms to
the original certified vehicle configuration.

Sec.  1037.130  Assembly instructions for secondary vehicle
manufacturers.

    (a) If you sell a certified incomplete vehicle to a secondary
vehicle manufacturer, give the secondary vehicle manufacturer
instructions for completing vehicle assembly consistent with the
requirements of this part. Include all information necessary to ensure
that the final vehicle assembly (including the engine for vehicles
other than trailers) will be in its certified configuration.
    (b) Make sure these instructions have the following information:
    (1) Include the heading: ``Emission-related installation
instructions''.
    (2) State: ``Failing to follow these instructions when completing
assembly of a heavy-duty motor vehicle violates federal law, subject to
fines or other penalties as described in the Clean Air Act.''
    (3) Describe the necessary steps for installing any diagnostic
system required under 40 CFR part 86.
    (4) Describe how your certification is limited for any type of
application, as illustrated in the following examples:
    (i) If the incomplete vehicle is at or below 8,500 pounds GVWR,
state that the vehicle's certification is valid under this part 1037
only if the final configuration has a vehicle curb weight above 6,000
pounds or basic vehicle frontal area above 45 square feet.
    (ii) If your engine will be installed in a vehicle that you certify
to meet diurnal emission standards using an evaporative canister, but
you do not install the fuel tank, identify the maximum permissible fuel
tank capacity.
    (5) Describe any other instructions to make sure the vehicle will
operate according to design specifications in your application for
certification.
    (c) Provide instructions in writing or in an equivalent format. You
may include this information with the incomplete vehicle document
required by DOT. If you do not provide the instructions in writing,
explain in your application for certification how you will ensure that
each installer is informed of the installation requirements.

Sec.  1037.135  Labeling.

    (a) Assign each vehicle a unique identification number and
permanently affix, engrave, or stamp it on the vehicle in a legible
way. The vehicle identification number (VIN) serves this purpose.
    (b) At the time of manufacture, affix a permanent and legible label
identifying each vehicle. The label must meet the requirements of 40
CFR 1068.45.
    (c) The label must--
    (1) Include the heading ``VEHICLE EMISSION CONTROL INFORMATION''.
    (2) Include your full corporate name and trademark. You may
identify another company and use its trademark instead of yours if you
comply with the branding provisions of 40 CFR 1068.45.
    (3) Include EPA's standardized designation for the vehicle family.
    (4) State the regulatory subcategory that determines the applicable
emission standards for the vehicle family (see definition in Sec.
1037.801).
    (5) State the date of manufacture [DAY (optional), MONTH, and
YEAR]. You may omit this from the label if you stamp, engrave, or
otherwise permanently identify it elsewhere on the vehicle, in which
case you must also describe in your application for certification where
you will identify the date on the vehicle.
    (6) Identify the emission control system. Use terms and
abbreviations as described in Appendix III to this part or other
applicable conventions. Phase 2 tractors and Phase 2 vocational
vehicles may omit this information.
    (7) Identify any requirements for fuel and lubricants that do not
involve fuel-sulfur levels.
    (8) State: ``THIS VEHICLE COMPLIES WITH U.S. EPA REGULATIONS FOR
[MODEL YEAR] HEAVY-DUTY VEHICLES.''
    (9) If you rely on another company to design and install fuel tanks
in incomplete vehicles that use an evaporative canister for controlling
diurnal emissions, include the following statement: ``THIS VEHICLE IS
DESIGNED TO COMPLY WITH EVAPORATIVE EMISSION STANDARDS WITH UP TO x
GALLONS OF FUEL TANK CAPACITY.'' Complete this statement by identifying
the maximum specified fuel tank capacity associated with your
certification.
    (d) You may add information to the emission control information
label as follows:
    (1) You may identify other emission standards that the vehicle
meets or does not meet (such as European standards).
    (2) You may add other information to ensure that the vehicle will
be properly maintained and used.
    (3) You may add appropriate features to prevent counterfeit labels.
For example, you may include the vehicle's unique identification number
on the label.

    (e) You may ask us to approve modified labeling requirements in
this part 1037 if you show that it is necessary or appropriate. We will
approve your request if your alternate label is consistent with the
requirements of this part.

Sec.  1037.140  Classifying vehicles and determining vehicle
parameters.

    (a) Where applicable, a vehicle's roof height and a trailer's
length are determined from nominal design specifications, as provided
in this section. Specify design values for roof height and trailer
length to the nearest inch.
    (b) Base roof height on fully inflated tires having a static loaded
radius equal to the arithmetic mean of the largest and smallest static
loaded radius of tires you offer or a standard tire we approve.
    (c) Base trailer length on the outer dimensions of the load-
carrying structure. Do not include aerodynamic devices or HVAC units.
    (d) The nominal design specifications must be within the range of
the actual values from production vehicles considering normal
production variability. In the case of roof height, use the mean tire
radius specified in paragraph (b) of this section. If after production
begins it is determined that your nominal design specifications do not
represent production vehicles, we may require you to amend your
application for certification under Sec.  1037.225.
    (e) If your vehicle is equipped with an adjustable roof fairing,
measure the roof height with the fairing in its lowest setting.
    (f) For any provisions in this part that depend on the number of
axles on a vehicle, include lift axles or any other installed axles
that can be used to carry the vehicle's weight while in motion.
    (g) The standards and other provisions of this part apply to
specific vehicle service classes for tractors and vocational vehicles
as follows:
    (1) Phase 1 and Phase 2 tractors are divided based on GVWR into
Class 7 tractors and Class 8 tractors. Where provisions apply to both
tractors and vocational vehicles, Class 7 tractors are considered
``Medium HDV'' and Class 8 tractors are considered ``Heavy HDV''.
    (2) Phase 1 vocational vehicles are divided based on GVWR. ``Light
HDV'' includes Class 2b through Class 5 vehicles; ``Medium HDV includes
Class 6 and Class 7 vehicles; and ``Heavy HDV includes Class 8
vehicles.
    (3) Phase 2 vocational vehicles with spark-ignition engines are
divided based on GVWR. ``Light HDV'' includes Class 2b through Class 5
vehicles, and ``Medium HDV includes Class 6 through Class 8 vehicles.
    (4) Phase 2 vocational vehicles with compression-ignition engines
are divided as follows:
    (i) Class 2b through Class 5 vehicles are considered ``Light HDV''.
    (ii) Class 6 through 8 vehicles are considered ``Heavy HDV'' if the
installed engine's primary intended service class is heavy heavy-duty
(see 40 CFR 1036.140). All other Class 6 through Class 8 vehicles are
considered ``Medium HDV''.
    (5) In certain circumstances, you may certify vehicles to standards
that apply for a different vehicle service class. For example, see
Sec. Sec.  1037.105(g) and 1037.106(f). If you optionally certify
vehicles to different standards, those vehicles are subject to all the
regulatory requirements as if the standards were mandatory.
    (h) Use good engineering judgment to identify the intended duty
cycle (Urban, Multi-Purpose, or Regional) for each of your vocational
vehicle configurations based on the expected use of the vehicles.

Sec.  1037.150  Interim provisions.

    The provisions in this section apply instead of other provisions in
this part.
    (a) Incentives for early introduction. The provisions of this
paragraph (a) apply with respect to tractors and vocational vehicles
produced in model years before 2014. Manufacturers may voluntarily
certify in model year 2013 (or earlier model years for electric
vehicles) to the greenhouse gas standards of this part.
    (1) This paragraph (a)(1) applies for regulatory subcategories
subject to the standards of Sec.  1037.105 or Sec.  1037.106. Except as
specified in paragraph (a)(3) of this section, to generate early
credits under this paragraph for any vehicles other than electric
vehicles, you must certify your entire U.S.-directed production volume
within the regulatory subcategory to these standards. Except as
specified in paragraph (a)(4) of this section, if some vehicle families
within a regulatory subcategory are certified after the start of the
model year, you may generate credits only for production that occurs
after all families are certified. For example, if you produce three
vehicle families in an averaging set and you receive your certificates
for those families on January 4, 2013, March 15, 2013, and April 24,
2013, you may not generate credits for model year 2013 production in
any of the families that occurs before April 24, 2013. Calculate
credits relative to the standard that would apply in model year 2014
using the equations in subpart H of this part. You may bank credits
equal to the surplus credits you generate under this paragraph (a)
multiplied by 1.50. For example, if you have 1.0 Mg of surplus credits
for model year 2013, you may bank 1.5 Mg of credits. Credit deficits
for an averaging set prior to model year 2014 do not carry over to
model year 2014. These credits may be used to show compliance with the
standards of this part for 2014 and later model years. We recommend
that you notify EPA of your intent to use this provision before
submitting your applications.
    (2) [Reserved]
    (3) You may generate emission credits for the number of additional
SmartWay designated tractors (relative to your 2012 production),
provided you do not generate credits for those vehicles under paragraph
(a)(1) of this section. Calculate credits for each regulatory
subcategory relative to the standard that would apply in model year
2014 using the equations in subpart H of this part. Use a production
volume equal to the number of designated model year 2013 SmartWay
tractors minus the number of designated model year 2012 SmartWay
tractors. You may bank credits equal to the surplus credits you
generate under this paragraph (a)(3) multiplied by 1.50. Your 2012 and
2013 model years must be equivalent in length.
    (4) This paragraph (a)(4) applies where you do not receive your
final certificate in a regulatory subcategory within 30 days of
submitting your final application for that subcategory. Calculate your
credits for all production that occurs 30 days or more after you submit
your final application for the subcategory.
    (b) Phase 1 coastdown procedures. For tractors subject to Phase 1
standards under Sec.  1037.106, the default method for measuring drag
area (CdA) is the coastdown procedure specified in 40 CFR
part 1066, subpart D. This includes preparing the tractor and the
standard trailer with wheels meeting specifications of Sec.
1037.528(b) and submitting information related to your coastdown
testing under Sec.  1037.528(h).
    (c) Provisions for small manufacturers. Standards apply on a
delayed schedule for manufacturers meeting the small business criteria
specified in 13 CFR 121.201. Apply the small business criteria for
NAICS code 336120 for vocational vehicles and tractors and 336212 for
trailers; the employee limits apply to the total number employees
together for affiliated companies. Qualifying small manufacturers are
not subject to the greenhouse gas standards of Sec. Sec.  1037.105 and
1037.106 for vehicles with a date of

manufacture before January 1, 2022, Similarly, qualifying small
manufacturers are not subject to the greenhouse gas standards of Sec.
1037.107 for trailers with a date of manufacture before January 1,
2019. In addition, qualifying small manufacturers producing vehicles
that run on any fuel other than gasoline, E85, or diesel fuel may delay
complying with every later standard under this part by one model year.
Qualifying manufacturers must notify the Designated Compliance Officer
each model year before introducing these excluded vehicles into U.S.
commerce. This notification must include a description of the
manufacturer's qualification as a small business under 13 CFR 121.201.
You must label your excluded vehicles with the following statement:
``THIS VEHICLE IS EXCLUDED UNDER 40 CFR 1037.150(c).'' Small
manufacturers may certify their vehicles under this part 1037 before
standards start to apply; however, they may generate emission credits
only if they certify their entire U.S.-directed production volume
within the applicable averaging set for that model year.
    (d) Air conditioning leakage for vocational vehicles. The air
conditioning leakage standard of Sec.  1037.115 does not apply for
model year 2020 and earlier vocational vehicles.
    (e) Delegated assembly. The delegated-assembly provisions of Sec.
1037.621 do not apply before January 1, 2018.
    (f) Electric vehicles. Tailpipe emissions of regulated pollutants
from electric vehicles (as defined in Sec.  1037.801) are deemed to be
zero. No emission testing is required for electric vehicles. Use good
engineering judgment to apply other requirements of this part to
electric vehicles.
    (g) Compliance date. Compliance with the standards of this part was
optional prior to January 1, 2014. This means that if your 2014 model
year begins before January 1, 2014, you may certify for a partial model
year that begins on January 1, 2014 and ends on the day your model year
would normally end. You must label model year 2014 vehicles excluded
under this paragraph (g) with the following statement: ``THIS VEHICLE
IS EXCLUDED UNDER 40 CFR 1037.150(g).''
    (h) Off-road vehicle exemption. (1) Vocational vehicles with a date
of manufacture before January 1, 2021 automatically qualify for an
exemption under Sec.  1037.631 if the tires installed on the vehicle
have a maximum speed rating at or below 55 miles per hour.
    (2) In unusual circumstances, vehicle manufacturers may ask us to
exempt vehicles under Sec.  1037.631 based on other criteria that are
equivalent to those specified in Sec.  1037.631(a); however, we will
normally not grant relief in cases where the vehicle manufacturer has
credits or can otherwise comply with applicable standards. Request
approval for an exemption under this paragraph (h) before you produce
the subject vehicles. Send your request with supporting information to
the Designated Compliance Officer; we will coordinate with NHTSA in
making a determination under Sec.  1037.210. If you introduce into U.S.
commerce vehicles that depend on our approval under this paragraph (h)
before we inform you of our approval, those vehicles violate 40 CFR
1068.101(a)(1).
    (i) Limited carryover from Phase 1 to Phase 2. The provisions for
carryover data in Sec.  1037.235(d) do not allow you to use aerodynamic
test results from Phase 1 to support a compliance demonstration for
Phase 2 certification.
    (j) Limited prohibition related to early model year engines. The
provisions of this paragraph (j) apply only for vehicles that have a
date of manufacture before January 1, 2018. See Sec.  1037.635 for
related provisions that apply in later model years. The prohibition in
Sec.  1037.601 against introducing into U.S. commerce a vehicle
containing an engine not certified to the standards applicable for the
calendar year of installation does not apply for vehicles using model
year 2014 or 2015 spark-ignition engines, or any model year 2013 or
earlier engines.
    (k) Verifying drag areas from in-use tractors. This paragraph (k)
applies for tractors instead of Sec.  1037.401(b) through model year
2020. We may measure the drag area of your vehicles after they have
been placed into service. To account for measurement variability, your
vehicle is deemed to conform to the regulations of this part with
respect to aerodynamic performance if we measure its drag area to be at
or below the maximum drag area allowed for the bin above the bin to
which you certified (for example, Bin II if you certified the vehicle
to Bin III), unless we determine that you knowingly produced the
vehicle to have a higher drag area than is allowed for the bin to which
it was certified.
    (l) Optional sister-vehicle certification under 40 CFR part 86. You
may certify certain complete or cab-complete vehicles to the GHG
standards of 40 CFR 86.1819 instead of the standards of Sec.  1037.105
as specified in 40 CFR 86.1819-14(j).
    (m) Loose engine sales. Manufacturers may certify certain spark-
ignition engines along with chassis-certified heavy-duty vehicles where
they are identical to engines used in those vehicles as described in 40
CFR 86.1819-14(k)(8). Vehicles in which those engines are installed are
subject to standards under this part as specified in Sec.  1037.105.
    (n) Transition to engine-based model years. The following
provisions apply for production and ABT reports during the transition
to engine-based model year determinations for tractors and vocational
vehicles in 2020 and 2021:
    (1) If you install model year 2020 or earlier engines in your
vehicles in calendar year 2020, include all those Phase 1 vehicles in
your production and ABT reports related to model year 2020 compliance,
although we may require you identify these separately from vehicles
produced in calendar year 2019.
    (2) If you install model year 2020 engines in your vehicles in
calendar year 2021, submit production and ABT reports for those Phase 1
vehicles separate from the reports you submit for Phase 2 vehicles with
model year 2021 engines.
    (o) Interim useful life for light heavy-duty vocational vehicles.
Class 2b through Class 5 vocational vehicles certified to Phase 1
standards are subject to a useful life of 110,000 miles or 10 years,
whichever comes first, instead of the useful life specified in Sec.
1037.105. For emission credits generated from these Phase 1 vehicles,
multiply any banked credits that you carry forward to demonstrate
compliance with Phase 2 standards by 1.36.
    (p) Credit multiplier for advanced technology. If you generate
credits from Phase 1 vehicles certified with advanced technology, you
may multiply these credits by 1.50, except that you may not apply this
multiplier in addition to the early-credit multiplier of paragraph (a)
of this section. If you generate credits from model year 2027 and
earlier Phase 2 vehicles certified with advanced technology, you may
multiply these credits by 3.5 for plug-in hybrid electric vehicles, 4.5
for electric vehicles, and 5.5 for fuel cell vehicles.
    (q) Vehicle families for advanced and off-cycle technologies. Apply
the following provisions for grouping vehicles into families if you use
off-cycle technologies under Sec.  1037.610 or advanced technologies
under Sec.  1037.615:
    (1) For vocational vehicles and tractors subject to Phase 1
standards, create separate vehicle families for vehicles that contain
advanced or off-

cycle technologies; group those vehicles together in a vehicle family
if they use the same advanced or off-cycle technologies.
    (2) For vocational vehicles and tractors subject to Phase 2
standards, create separate vehicle families if there is a credit
multiplier for advanced technology; group those vehicles together in a
vehicle family if they use the same multiplier.
    (r) Conversion to mid- roof and high-roof configurations. Secondary
vehicle manufacturers that qualify as small manufacturers may convert
low- and mid-roof tractors to mid- and high-roof configurations without
recertification for the purpose of building a custom sleeper tractor or
converting it to run on natural gas, as follows:
    (1) The original low- or mid-roof tractor must be covered by a
valid certificate of conformity.
    (2) The modifications may not increase the frontal area of the
tractor beyond the frontal area of the equivalent mid- or high-roof
tractor with the corresponding standard trailer. Note that these
dimensions have a tolerance of 2 inches. Use good
engineering judgment to achieve aerodynamic performance similar to or
better than the certifying manufacturer's corresponding mid- or high-
roof tractor.
    (3) Add a permanent supplemental label to the vehicle near the
original manufacturer's emission control information label. On the
label identify your full corporate name and include the following
statement: ``THIS VEHICLE WAS MODIFIED AS ALLOWED UNDER 40 CFR
1037.150.''
    (4) We may require that you submit annual production reports as
described in Sec.  1037.250.
    (5) Modifications made under this paragraph (r) do not violate 40
CFR 1068.101(b)(1).
    (s) Confirmatory testing for Falt-aero. If we conduct
coastdown testing to verify your Falt-aero value for Phase 2
tractors, we will make our determination using a statistical analysis
consistent with the principles of SEA testing in Sec.  1037.305. We
will calculate confidence intervals using the same equations and will
not replace your test results with ours if your result falls within our
confidence interval or is greater than our test result.
    (t) Glider kits and glider vehicles. (1) Glider vehicles conforming
to the requirements in this paragraph (t)(1) are exempt from the Phase
1 emission standards of this part 1037 prior to January 1, 2021.
Engines in such vehicles (including vehicles produced after January 1,
2021) remain subject to the requirements of 40 CFR part 86 applicable
for the engines' original model year, but not subject to the Phase 1 or
Phase 2 standards of 40 CFR part 1036 unless they were originally
manufactured in model year 2014 or later.
    (i) You are eligible for this exemption if you are a small
manufacturer and you sold one or more glider vehicles in 2014 under the
provisions of Sec.  1037.150(c). You do not qualify if you only
produced glider vehicles for your own use. You must notify us of your
plans to use this exemption before you introduce exempt vehicles into
U.S. commerce. In your notification, you must identify your annual
U.S.-directed production volume (and sales, if different) of such
vehicles for calendar years 2010 through 2014. Vehicles you produce
before notifying us are not exempt under this section.
    (ii) In a given calendar year, you may produce up to 300 exempt
vehicles under this section, or up to the highest annual production
volume you identify in paragraph (t)(1) of this section, whichever is
less.
    (iii) Identify the number of exempt vehicles you produced under
this exemption for the preceding calendar year in your annual report
under Sec.  1037.250.
    (iv) Include the appropriate statement on the label required under
Sec.  1037.135, as follows:
    (A) For Phase 1 vehicles, ``THIS VEHICLE AND ITS ENGINE ARE EXEMPT
UNDER 40 CFR 1037.150(t)(1).''
    (B) For Phase 2 vehicles, ``THE ENGINE IN THIS VEHICLE IS EXEMPT
UNDER 40 CFR 1037.150(t)(1).''
    (v) If you produce your glider vehicle by installing remanufactured
or previously used components in a glider kit produced by another
manufacturer, you must provide the following to the glider kit
manufacturer prior to obtaining the glider kit:
    (A) Your name, the name of your company, and contact information.
    (B) A signed statement that you are a qualifying small manufacturer
and that your production will not exceed the production limits of this
paragraph (t)(1). This statement is deemed to be a submission to EPA,
and we may require the glider kit manufacturer to provide a copy to us
at any time.
    (vi) This exemption is valid for a given vehicle and engine only if
you meet all the requirements and conditions of this paragraph (t)(1)
that apply with respect to that vehicle and engine. Introducing such a
vehicle into U.S. commerce without meeting all applicable requirements
and conditions violates 40 CFR 1068.101(a)(1).
    (vii) Companies that are not small manufacturers may sell
uncertified incomplete vehicles without engines to small manufacturers
for the purpose of producing exempt vehicles under this paragraph
(t)(1), subject to the provisions of Sec.  1037.622. However, such
companies must take reasonable steps to ensure that their incomplete
vehicles will be used in conformance with the requirements of this part
1037.
    (2) Glider vehicles produced using engines certified to model year
2010 or later standards for all pollutants are subject to the same
provisions that apply to vehicles using engines within their useful
life in Sec.  1037.635.
    (3) For calendar year 2017, you may produce a limited number of
glider kits and/or glider vehicles subject to the requirements
applicable to model year 2016 glider vehicles, instead of the
requirements of Sec.  1037.635. The limit applies to your combined 2017
production of glider kits and glider vehicles and is equal to your
highest annual production of glider kits and glider vehicles for any
year from 2010 to 2014. Any glider kits or glider vehicles produced
beyond this cap are subject to the provisions of Sec.  1037.635. Count
any glider kits and glider vehicles you produce under paragraph (t)(1)
of this section as part of your production with respect to this
paragraph (t)(3).
    (u) Streamlined preliminary approval for trailer devices. Before
January 1, 2018, manufacturers of aerodynamic devices for trailers may
ask for preliminary EPA approval of compliance data for their devices
based on qualifying for designation under the SmartWay program based on
measured CdA values, whether or not that involves testing or
other methods specified in Sec.  1037.526. Trailer manufacturers may
certify based on [Delta]CdA values established under this
paragraph (u) through model year 2020. Manufacturers must perform
testing as specified in subpart F of this part for any vehicles or
aerodynamic devices not qualifying for approval under this paragraph
(u).
    (v) Transitional allowances for trailers. Through model year 2026,
trailer manufacturers may calculate a number of trailers that are
exempt from the standards and certification requirements of this part.
Calculate the number of exempt box vans in a given model year by
multiplying your total U.S.-directed production volume of certified box
vans by 0.20 and rounding to the nearest whole number; however, in no
case may the number of exempted box vans be greater than 350 units in
any given model year. Repeat this calculation to determine the number
of non-box trailers, up to 250 annual units, that are exempt from
standards and certification requirements. Perform the

calculation based on your projected production volumes in the first
year that standards apply; in later years, use actual production
volumes from the preceding model year. Include these calculated values
and your production volumes of exempt trailers in your annual
production report under Sec.  1037.250. You must apply a label meeting
the requirements of 40 CFR 1068.45(a) that identifies your corporate
name and states that the trailer is exempt under the provisions of
Sec.  1037.150. Unlabeled trailers will be considered in violation of
40 CFR 1068.101(a)(1).
    (w) Roll-up doors for non-aero box vans. Through model year 2023,
box vans may qualify for non-aero or partial-aero standards under Sec.
1037.107 by treating roll-up rear doors as being equivalent to rear
lift gates.
    (x) Aerodynamic testing for trailers. Section 1037.526 generally
requires you to adjust [Delta]CdA values from alternate test
methods to be equivalent to measurements with the primary test method.
This paragraph (x) describes approximations that we believe are
consistent with good engineering judgment; however, you may not use
these approximations where we determine that clear and convincing
evidence shows that they would significantly overestimate actual
improvements in aerodynamic performance.
    (1) You may presume that CFD measurements at a yaw angle of
4.5[deg] are equal to measurements made using the primary method, and
you may use them without adjustment.
    (2) You may presume that coastdown measurements at yaw angles
smaller than  4.5[deg] are equal to measurements made using
the primary method, and you may use them without adjustment. This
applies equally for device manufacturers, but it does not apply for EPA
testing.
    (3) You may use testing or analytical methods to adjust coastdown
measurements to account for aerodynamic effects at a yaw angle of
4.5[deg]. This applies for rear fairings and other devices
whose performance is affected by yaw angle.
    (y) Transition to Phase 2 standards. The following provisions allow
for enhanced generation and use of emission credits from Phase 1
tractors and vocational vehicles for meeting the Phase 2 standards:
    (1) For vocational Light HDV and vocational Medium HDV, emission
credits you generate in model years 2018 through 2021 may be used
through model year 2027, instead of being limited to a five-year credit
life as specified in Sec.  1037.740(c). For Class 8 vocational vehicles
with medium heavy-duty engines, we will approve your request to
generate these credits in and use these credits for the Medium HDV
averaging set if you show that these vehicles would qualify as Medium
HDV under the Phase 2 program as described in Sec.  1037.140(g)(4).
    (2) You may use the off-cycle provisions of Sec.  1037.610 to apply
technologies to Phase 1 vehicles as follows:
    (i) You may apply an improvement factor of 0.988 for tractors and
vocational vehicles with automatic tire inflation systems on all axles.
    (ii) For vocational vehicles with automatic engine shutdown systems
that conform with Sec.  1037.660, you may apply an improvement factor
of 0.95.
    (iii) For vocational vehicles with stop-start systems that conform
with Sec.  1037.660, you may apply an improvement factor of 0.92.
    (iv) For vocational vehicles with neutral-idle systems conforming
with Sec.  1037.660, you may apply an improvement factor of 0.98. You
may adjust this improvement factor if we approve a partial reduction
under Sec.  1037.660(a)(2); for example, if your design reduces fuel
consumption by half as much as shifting to neutral, you may apply an
improvement factor of 0.99.
    (3) Small manufacturers may generate emission credits for natural
gas-fueled vocational vehicles as follows:
    (i) Small manufacturers may certify their vehicles instead of
relying on the exemption of paragraph (c) of this section. The
provisions of this part apply for such vehicles, except as specified in
this paragraph (y)(3).
    (ii) Use Phase 1 GEM to determine a CO2 emission level
for your vehicle, then multiply this value by the engine's FCL for
CO2 and divide by the engine's applicable CO2
emission standard.
    (z) Constraints for vocational duty cycles. The following
provisions apply to determinations of vocational duty cycles as
described in Sec.  1037.140:
    (1) The Regional duty cycle applies if the engine was certified
based on testing only with the ramped-modal cycle.
    (2) The Regional duty cycle applies for coach buses and motor homes
you certify under Sec.  1037.105(b).
    (3) You may not select the Urban duty cycle for any vehicle with a
manual or single-clutch automated manual transmission.
    (4) Starting in model year 2024, you must select the Regional duty
cycle for any vehicle with a manual transmission.
    (5) You may select the Urban duty cycle for a hybrid vehicle
equipped with regenerative braking, unless it is equipped with a manual
transmission.
    (6) You may select the Urban duty cycle for any vehicle with a
hydrokinetic torque converter paired with an automatic transmission, or
a continuously variable automatic transmission, or a dual-clutch
transmission with no more than two consecutive forward gears between
which it is normal for both clutches to be momentarily disengaged.
    (aa) Custom-chassis standards. The following provisions apply
uniquely to small manufacturers under the custom-chassis standards of
Sec.  1037.105(h):
    (1) You may use emission credits generated under Sec.  1037.105(d),
including banked or traded credits from any averaging set. Such credits
remain subject to other limitations that apply under subpart H of this
part.
    (2) You may produce up to 200 drayage tractors in a given model
year to the standards described in Sec.  1037.105(h) for ``other
buses''. Treat these drayage tractors as being in their own averaging
set.

Subpart C--Certifying Vehicle Families

Sec.  1037.201  General requirements for obtaining a certificate of
conformity.

    (a) You must send us a separate application for a certificate of
conformity for each vehicle family. A certificate of conformity is
valid from the indicated effective date until the end of the model year
for which it is issued. You must renew your certification annually for
any vehicles you continue to produce.
    (b) The application must contain all the information required by
this part and must not include false or incomplete statements or
information (see Sec.  1037.255).
    (c) We may ask you to include less information than we specify in
this subpart, as long as you maintain all the information required by
Sec.  1037.250.
    (d) You must use good engineering judgment for all decisions
related to your application (see 40 CFR 1068.5).
    (e) An authorized representative of your company must approve and
sign the application.
    (f) See Sec.  1037.255 for provisions describing how we will
process your application.
    (g) We may perform confirmatory testing on your vehicles or
components; for example, we may test vehicles to verify drag areas or
other GEM inputs. This includes tractors used to determine
Falt-aero under Sec.  1037.525. We may require you to
deliver your test vehicles or components to a facility we designate for
our testing. Alternatively, you may

choose to deliver another vehicle or component that is identical in all
material respects to the test vehicle or component, or a different
vehicle or component that we determine can appropriately serve as an
emission-data vehicle for the family. We may perform confirmatory
testing on engines under 40 CFR part 1036 and may require you to apply
modified fuel maps from that testing for certification under this part.
    (h) The certification and testing provisions of 40 CFR part 86,
subpart S, apply instead of the provisions of this subpart relative to
the evaporative and refueling emission standards specified in Sec.
1037.103, except that Sec.  1037.245 describes how to demonstrate
compliance with evaporative emission standards. For vehicles that do
not use an evaporative canister for controlling diurnal emissions, you
may certify with respect to exhaust emissions and use the provisions of
Sec.  1037.622 to let a different company certify with respect to
evaporative emissions.
    (i) Vehicles and installed engines must meet exhaust, evaporative,
and refueling emission standards and certification requirements in 40
CFR part 86 or 40 CFR part 1036, as applicable. Include the information
described in 40 CFR part 86, subpart S, or 40 CFR 1036.205 in your
application for certification in addition to what we specify in Sec.
1037.205 so we can issue a single certificate of conformity for all the
requirements that apply for your vehicle and the installed engine.

Sec.  1037.205  What must I include in my application?

    This section specifies the information that must be in your
application, unless we ask you to include less information under Sec.
1037.201(c). We may require you to provide additional information to
evaluate your application. References to testing and emission-data
vehicles refer to testing vehicles or components to measure any
quantity that serves as an input value for modeling emission rates
under Sec.  1037.515 or 1037.520.
    (a) Describe the vehicle family's specifications and other basic
parameters of the vehicle's design and emission controls. List the fuel
type on which your vocational vehicles and tractors are designed to
operate (for example, ultra-low-sulfur diesel fuel).
    (b) Explain how the emission control system operates. As
applicable, describe in detail all system components for controlling
greenhouse gas emissions, including all auxiliary emission control
devices (AECDs) and all fuel-system components you will install on any
production vehicle. Identify the part number of each component you
describe. For this paragraph (b), treat as separate AECDs any devices
that modulate or activate differently from each other. Also describe
your modeling inputs as described in Sec. Sec.  1037.515 and 1037.520,
with the following additional information if it applies for your
vehicles:
    (1) Describe your design for vehicle speed limiters, consistent
with Sec.  1037.640.
    (2) Describe your design for predictive cruise control.
    (3) Describe your design for automatic engine shutdown systems,
consistent with Sec.  1037.660.
    (4) Describe your engineering analysis demonstrating that your air
conditioning compressor qualifies as a high-efficiency model as
described in 40 CFR 86.1868-12(h)(5).
    (5) Describe your design for idle-reduction technology, including
the logic for engine shutdown and the maximum duration of engine
operation after the onset of any vehicle conditions described in Sec.
1037.660.
    (6) If you perform powertrain testing under Sec.  1037.550, report
both CO2 and NOX emission levels corresponding to
each test run.
    (7) Describe the configuration and basic design of hybrid systems.
Include measurements for vehicles with hybrid power take-off systems.
    (8) If you install auxiliary power units in tractors under Sec.
1037.106(g), identify the family name associated with the engine's
certification under 40 CFR part 1039. Starting in model year 2024, also
identify the family name associated with the auxiliary power unit's
certification to the standards of 40 CFR 1039.699.
    (9) Describe how you meet any applicable criteria in Sec.
1037.631(a)(1) and (2).
    (c) For vehicles subject to air conditioning standards, include:
    (1) The refrigerant leakage rates (leak scores).
    (2) The type of refrigerant and the refrigerant capacity of the air
conditioning systems.
    (3) The corporate name of the final installer of the air
conditioning system.
    (d) Describe any vehicles or components you selected for testing
and the reasons for selecting them.
    (e) Describe any test equipment and procedures that you used,
including any special or alternate test procedures you used (see Sec.
1037.501). Include information describing the procedures you used to
determine CdA values as specified in Sec. Sec.  1037.525
through 1037.527. Describe which type of data you are using for engine
fuel maps (see 40 CFR 1036.510). If your trailer certification relies
on approved data from device manufacturers, identify the device and
device manufacturer.
    (f) Describe how you operated any emission-data vehicle before
testing, including the duty cycle and the number of vehicle operating
miles used to stabilize emission-related performance. Explain why you
selected the method of service accumulation. Describe any scheduled
maintenance you did.
    (g) Where applicable, list the specifications of any test fuel to
show that it falls within the required ranges we specify in 40 CFR part
1065.
    (h) Identify the vehicle family's useful life.
    (i) Include the maintenance instructions and warranty statement you
will give to the ultimate purchaser of each new vehicle (see Sec. Sec.
1037.120 and 1037.125).
    (j) Describe your emission control information label (see Sec.
1037.135).
    (k) Identify the emission standards or FELs to which you are
certifying vehicles in the vehicle family. For families containing
multiple subfamilies, this means that you must identify the highest and
lowest FELs to which any of your subfamilies will be certified.
    (l) Where applicable, identify the vehicle family's deterioration
factors and describe how you developed them. Present any emission test
data you used for this (see Sec.  1037.241(c)).
    (m) Where applicable, state that you operated your emission-data
vehicles as described in the application (including the test
procedures, test parameters, and test fuels) to show you meet the
requirements of this part.
    (n) [Reserved]
    (o) Report calculated and modeled emission results as follows:
    (1) For vocational vehicles and tractors, report modeling results
for ten configurations. Include modeling inputs and detailed
descriptions of how they were derived. Unless we specify otherwise,
include the configuration with the highest modeling result, the lowest
modeling result, and the configurations with the highest projected
sales.
    (2) For trailers that demonstrate compliance with g/ton-mile
emission standards as described in Sec.  1037.515, report the
CO2 emission result for the configuration with the highest
calculated value. If your trailer family generates or uses emission
credits, also report the CO2 emission results for the
configuration with the lowest calculated value, and for the
configuration with the highest projected sales.

    (p) Where applicable, describe all adjustable operating parameters
(see Sec.  1037.115), including production tolerances. You do not need
to include parameters that do not affect emissions covered by your
application. Include the following in your description of each
parameter:
    (1) The nominal or recommended setting.
    (2) The intended physically adjustable range.
    (3) The limits or stops used to establish adjustable ranges.
    (4) Information showing why the limits, stops, or other means of
inhibiting adjustment are effective in preventing adjustment of
parameters on in-use vehicles to settings outside your intended
physically adjustable ranges.
    (q) [Reserved]
    (r) Unconditionally certify that all the vehicles in the vehicle
family comply with the requirements of this part, other referenced
parts of the CFR, and the Clean Air Act.
    (s) Include good-faith estimates of U.S.-directed production
volumes by subfamily. We may require you to describe the basis of your
estimates.
    (t) Include the information required by other subparts of this
part. For example, include the information required by Sec.  1037.725
if you plan to generate or use emission credits.
    (u) Include other applicable information, such as information
specified in this part or 40 CFR part 1068 related to requests for
exemptions.
    (v) Name an agent for service located in the United States. Service
on this agent constitutes service on you or any of your officers or
employees for any action by EPA or otherwise by the United States
related to the requirements of this part.

Sec.  1037.210  Preliminary approval before certification.

    If you send us information before you finish the application, we
may review it and make any appropriate determinations. Decisions made
under this section are considered to be preliminary approval, subject
to final review and approval. We will generally not reverse a decision
where we have given you preliminary approval, unless we find new
information supporting a different decision. If you request preliminary
approval related to the upcoming model year or the model year after
that, we will make best-efforts to make the appropriate determinations
as soon as practicable. We will generally not provide preliminary
approval related to a future model year more than two years ahead of
time.

Sec.  1037.211  Preliminary approval for manufacturers of aerodynamic
devices.

    (a) If you design or manufacture aerodynamic devices for trailers,
you may ask us to provide preliminary approval for the measured
performance of your devices. While decisions made under this section
are considered to be preliminary approval, we will not reverse a
decision where we have given you preliminary approval, unless we find
new information supporting a different decision. For example, where we
measure the performance of your device after giving you preliminary
approval and its measured performance is less than your data indicated,
we may rescind the preliminary approval of your test results.
    (b) To request this, you must provide test data for
[Delta]CdA values as specified in Sec.  1037.150(u) or Sec.
1037.526. Trailer manufacturers may use approved [Delta]CdA
values as inputs under Sec.  1037.515 to support their application for
certification.

Sec.  1037.220  Amending maintenance instructions.

    You may amend your emission-related maintenance instructions after
you submit your application for certification as long as the amended
instructions remain consistent with the provisions of Sec.  1037.125.
You must send the Designated Compliance Officer a written request to
amend your application for certification for a vehicle family if you
want to change the emission-related maintenance instructions in a way
that could affect emissions. In your request, describe the proposed
changes to the maintenance instructions. If operators follow the
original maintenance instructions rather than the newly specified
maintenance, this does not allow you to disqualify those vehicles from
in-use testing or deny a warranty claim.
    (a) If you are decreasing or eliminating any specified maintenance,
you may distribute the new maintenance instructions to your customers
30 days after we receive your request, unless we disapprove your
request. This would generally include replacing one maintenance step
with another. We may approve a shorter time or waive this requirement.
    (b) If your requested change would not decrease the specified
maintenance, you may distribute the new maintenance instructions any
time after you send your request. For example, this paragraph (b) would
cover adding instructions to increase the frequency of filter changes
for vehicles in severe-duty applications.
    (c) You need not request approval if you are making only minor
corrections (such as correcting typographical mistakes), clarifying
your maintenance instructions, or changing instructions for maintenance
unrelated to emission control. We may ask you to send us copies of
maintenance instructions revised under this paragraph (c).

Sec.  1037.225  Amending applications for certification.

    Before we issue you a certificate of conformity, you may amend your
application to include new or modified vehicle configurations, subject
to the provisions of this section. After we have issued your
certificate of conformity, you may send us an amended application
requesting that we include new or modified vehicle configurations
within the scope of the certificate, subject to the provisions of this
section. You must amend your application if any changes occur with
respect to any information that is included or should be included in
your application.
    (a) You must amend your application before you take any of the
following actions:
    (1) Add any vehicle configurations to a vehicle family that are not
already covered by your application. For example, if your application
identifies three possible engine models, and you plan to produce
vehicles using an additional engine model, then you must amend your
application before producing vehicles with the fourth engine model. The
added vehicle configurations must be consistent with other vehicle
configurations in the vehicle family with respect to the criteria
listed in Sec.  1037.230.
    (2) Change a vehicle configuration already included in a vehicle
family in a way that may change any of the components you described in
your application for certification, or make any other changes that
would make the emissions inconsistent with the information in your
application. This includes production and design changes that may
affect emissions any time during the vehicle's lifetime.
    (3) Modify an FEL for a vehicle family as described in paragraph
(f) of this section.
    (b) To amend your application for certification, send the relevant
information to the Designated Compliance Officer.
    (1) Describe in detail the addition or change in the vehicle model
or configuration you intend to make.
    (2) Include engineering evaluations or data showing that the
amended vehicle family complies with all applicable requirements. You
may do this by

showing that the original emission-data vehicle is still appropriate
for showing that the amended family complies with all applicable
requirements.
    (3) If the original emission-data vehicle or emission modeling for
the vehicle family is not appropriate to show compliance for the new or
modified vehicle configuration, include new test data or emission
modeling showing that the new or modified vehicle configuration meets
the requirements of this part.
    (4) Include any other information needed to make your application
correct and complete.
    (c) We may ask for more test data or engineering evaluations. You
must give us these within 30 days after we request them.
    (d) For vehicle families already covered by a certificate of
conformity, we will determine whether the existing certificate of
conformity covers your newly added or modified vehicle. You may ask for
a hearing if we deny your request (see Sec.  1037.820).
    (e) For vehicle families already covered by a certificate of
conformity, you may start producing the new or modified vehicle
configuration any time after you send us your amended application and
before we make a decision under paragraph (d) of this section. However,
if we determine that the affected vehicles do not meet applicable
requirements, we will notify you to cease production of the vehicles
and may require you to recall the vehicles at no expense to the owner.
Choosing to produce vehicles under this paragraph (e) is deemed to be
consent to recall all vehicles that we determine do not meet applicable
emission standards or other requirements and to remedy the
nonconformity at no expense to the owner. If you do not provide
information required under paragraph (c) of this section within 30 days
after we request it, you must stop producing the new or modified
vehicles.
    (f) You may ask us to approve a change to your FEL in certain cases
after the start of production. The changed FEL may not apply to
vehicles you have already introduced into U.S. commerce, except as
described in this paragraph (f). You may ask us to approve a change to
your FEL in the following cases:
    (1) You may ask to raise your FEL for your vehicle subfamily at any
time. In your request, you must show that you will still be able to
meet the emission standards as specified in subparts B and H of this
part. Use the appropriate FELs with corresponding production volumes to
calculate emission credits for the model year, as described in subpart
H of this part.
    (2) Where testing applies, you may ask to lower the FEL for your
vehicle subfamily only if you have test data from production vehicles
showing that emissions are below the proposed lower FEL. Otherwise, you
may ask to lower your FEL for your vehicle subfamily at any time. The
lower FEL applies only to vehicles you produce after we approve the new
FEL. Use the appropriate FELs with corresponding production volumes to
calculate emission credits for the model year, as described in subpart
H of this part.
    (3) You may ask to add an FEL for your vehicle family at any time.
    (g) You may produce vehicles as described in your amended
application for certification and consider those vehicles to be in a
certified configuration if we approve a new or modified vehicle
configuration during the model year under paragraph (d) of this
section. Similarly, you may modify in-use vehicles as described in your
amended application for certification and consider those vehicles to be
in a certified configuration if we approve a new or modified vehicle
configuration at any time under paragraph (d) of this section.
Modifying a new or in-use vehicle to be in a certified configuration
does not violate the tampering prohibition of 40 CFR 1068.101(b)(1), as
long as this does not involve changing to a certified configuration
with a higher family emission limit. See Sec.  1037.621(g) for special
provisions that apply for changing to a different certified
configuration in certain circumstances.

Sec.  1037.230  Vehicle families, sub-families, and configurations.

    (a) For purposes of certifying your vehicles to greenhouse gas
standards, divide your product line into families of vehicles based on
regulatory subcategories as specified in this section. Subcategories
are specified using terms defined in Sec.  1037.801. Your vehicle
family is limited to a single model year.
    (1) Apply subcategories for vocational vehicles and vocational
tractors as shown in Table 1 of this section. This involves 15 separate
subcategories for Phase 2 vehicles to account for engine
characteristics, GVWR, and the selection of duty cycle for vocational
vehicles as specified in Sec.  1037.510; vehicles may additionally fall
into one of the subcategories defined by the custom-chassis standards
in Sec.  1037.105(h). Divide Phase 1 vehicles into three GVWR-based
vehicle service classes as shown in Table 1 of this section,
disregarding additional specified characteristics. Table 1 follows:

                          Table 1 of Sec.   1037.230--Vocational Vehicle Subcategories
----------------------------------------------------------------------------------------------------------------
             Engine cycle                     Light HDV                Medium HDV               Heavy HDV
----------------------------------------------------------------------------------------------------------------
Compression-ignition.................  Urban..................  Urban..................  Urban.
                                       Multi-Purpose..........  Multi-Purpose..........  Multi-Purpose.
                                       Regional...............  Regional...............  Regional.
Spark-ignition.......................  Urban..................  Urban..................
                                       Multi-Purpose..........  Multi-Purpose..........
                                       Regional...............  Regional...............
----------------------------------------------------------------------------------------------------------------

    (2) Apply subcategories for tractors (other than vocational
tractors) as shown in Table 2 of this section. Vehicles may
additionally fall into one of the subcategories defined by the optional
tractor standards in Sec.  1037.670.

            Table 2 of Sec.   1037.230--Tractor Subcategories
------------------------------------------------------------------------

------------------------------------------------------------------------
Class 7                                           Class 8
------------------------------------------------------------------------
Low-roof tractors...............  Low-roof day cabs.  Low-roof sleeper
                                                       cabs.
Mid-roof tractors...............  Mid-roof day cabs.  Mid-roof sleeper
                                                       cabs.
High-roof tractors..............  High-roof day cabs  High-roof sleeper
                                                       cabs.
                                 ---------------------------------------
                                    Heavy-haul tractors (starting with
                                                 Phase 2).
------------------------------------------------------------------------

    (3) Apply subcategories for trailers as shown in the following
table:

            Table 3 of Sec.   1037.230--Trailer Subcategories
------------------------------------------------------------------------
                                     Partial-aero
       Full-aero trailers              trailers         Other trailers
------------------------------------------------------------------------
Long dry box vans...............  Long dry box vans.  Non-aero trailers.
Short dry box vans..............  Short dry box vans  Non-box trailers.
Long refrigerated box vans......  Long refrigerated
                                   box vans..
Short refrigerated box vans.....  Short refrigerated
                                   box vans..
------------------------------------------------------------------------

    (b) If the vehicles in your family are being certified to more than
one FEL, subdivide your greenhouse gas vehicle families into
subfamilies that include vehicles with identical FELs. Note that you
may add subfamilies at any time during the model year.
    (c) Group vehicles into configurations consistent with the
definition of ``vehicle configuration'' in Sec.  1037.801. Note that
vehicles with hardware or software differences that are related to
measured or modeled emissions are considered to be different vehicle
configurations even if they have the same modeling inputs and FEL. Note
also, that you are not required to separately identify all
configurations for certification. Note that you are not required to
identify all possible configurations for certification; also, you are
required to include in your end-of-year report only those
configurations you produced.
    (d) You may combine dissimilar vehicles into a single vehicle
family in special circumstances as follows:
    (1) For a Phase 1 vehicle model that straddles a roof-height, cab
type, or GVWR division, you may include all the vehicles in the same
vehicle family if you certify the vehicle family to the more stringent
standard. For roof height, this means you must certify to the taller
roof standards. For cab-type and GVWR, this means you must certify to
the numerically lower standards.
    (2) For a Phase 2 vehicle model that includes a range of GVWR
values that straddle weight classes, you may include all the vehicles
in the same vehicle family if you certify the vehicle family to the
numerically lower CO2 emission standard from the affected
service classes. Vehicles that are optionally certified to a more
stringent standard under this paragraph (d)(2) are subject to useful-
life and all other provisions corresponding to the weight class with
the numerically lower CO2 emission standard. For a Phase 2
tractor model that includes a range of roof heights that straddle
subcategories, you may include all the vehicles in the same vehicle
family if you certify the vehicle family to the appropriate subcategory
as follows:
    (i) You may certify mid-roof tractors as high-roof tractors, but
you may not certify high-roof tractors as mid-roof tractors.
    (ii) For tractor families straddling the low-roof/mid-roof
division, you may certify the family based on the primary roof-height
as long as no more than 10 percent of the tractors are certified to the
otherwise inapplicable subcategory. For example, if 95 percent of the
tractors in the family are less than 120 inches tall, and the other 5
percent are 122 inches tall, you may certify the tractors as a single
family in the low-roof subcategory.
    (iii) Determine the appropriate aerodynamic bin number based on the
actual roof height if you measure a CdA value. However, use
the GEM input for the bin based on the standards to which you certify.
For example, of you certify as mid-roof tractors some low-roof tractors
with a measured CdA value of 4.2 m\2\, they qualify as Bin
IV; and you must input into GEM the mid-roof Bin IV value of 5.85 m\2\.
    (3) You may include refrigerated box vans in a vehicle family with
dry box vans by treating them all as dry box vans for demonstrating
compliance with emission standards. You may include certain other types
of trailers in a vehicle family with a different type of trailer, such
that the combined set of trailers are all subject to the more stringent
standards, as follows:
    (i) Standards for long trailers are more stringent than standards
for short trailers.
    (ii) Standards for long dry box vans are more stringent than
standards for short refrigerated box vans.
    (iii) Standards for non-aero box vans are more stringent than
standards for non-box trailers.
    (e) You may divide your families into more families than specified
in this section.
    (f) You may ask us to allow you to group into the same
configuration vehicles that have very small body hardware differences
that do not significantly affect drag areas.

Sec.  1037.231  Powertrain families.

    (a) If you choose to perform powertrain testing as specified in
Sec.  1037.550, use good engineering judgment to divide your product
line into powertrain families that are expected to have similar fuel
consumptions and CO2 emission characteristics throughout the
useful life. Your powertrain family is limited to a single model year.
    (b) Except as specified in paragraph (c) of this section, group
powertrains in the same powertrain family if they share all the
following attributes:
    (1) Engine family.
    (2) Shared vehicle service class grouping, as follows:
    (i) Light HDV or Medium HDV.
    (ii) Heavy HDV other than heavy-haul tractors.
    (iii) Heavy-haul tractors.
    (3) Number of clutches.
    (4) Type of clutch (e.g., wet or dry).
    (5) Presence and location of a fluid coupling such as a torque
converter.
    (6) Gear configuration, as follows:
    (i) Planetary (e.g., simple, compound, meshed-planet, stepped-
planet, multi-stage).
    (ii) Countershaft (e.g., single, double, triple).
    (iii) Continuously variable (e.g., pulley, magnetic, toroidal).
    (7) Number of available forward gears, and transmission gear ratio
for each available forward gear, if applicable.
    (8) Transmission oil sump configuration (e.g., conventional or
dry).
    (9) The power transfer configuration of any hybrid technology
(e.g., series or parallel).
    (10) The energy storage device and capacity of any hybrid
technology (e.g., 10 MJ hydraulic accumulator, 10 kW[middot]hr Lithium-
ion battery pack, 10 MJ ultracapacitor bank).
    (11) The rated output of any hybrid mechanical power technology
(e.g., 50 kW electric motor).
    (c) For powertrains that share all the attributes described in
paragraph (b) of this section, divide them further into separate
powertrain families based on common calibration attributes. Group
powertrains in the same powertrain

family to the extent that powertrain test results and corresponding
emission levels are expected to be similar throughout the useful life.
    (d) You may subdivide a group of powertrains with shared attributes
under paragraph (b) of this section into different powertrain families.
    (e) In unusual circumstances, you may group powertrains into the
same powertrain family even if they do not have shared attributes under
in paragraph (b) of this section if you show that their emission
characteristics throughout the useful life will be similar.
    (f) If you include the axle when performing powertrain testing for
the family, you must limit the family to include only those axles
represented by the test results. You may include multiple axle ratios
in the family if you test with the axle expected to produce the highest
emission results.

Sec.  1037.232  Axle and transmission families.

    (a) If you choose to perform axle testing as specified in Sec.
1037.560 or transmission testing as specified in Sec.  1037.565, use
good engineering judgment to divide your product line into axle or
transmission families that are expected to have similar hardware,
noting that efficiencies can differ across the members of a family.
Note that, while there is no certification for axle and transmission
families under this part, vehicle manufacturers may rely on axle and
transmission test data to certify their vehicles.
    (b) Except as specified in paragraph (d) of this section, group
axles in the same axle family if they have the same number of drive
axles and the same load rating.
    (c) Except as specified in paragraph (d) of this section, group
transmissions in the same transmission family if they share all the
following attributes:
    (1) Number and type of clutches (wet or dry).
    (2) Presence and location of a fluid coupling such as a torque
converter.
    (3) Gear configuration, as follows:
    (i) Planetary (e.g., simple, compound, meshed-planet, stepped-
planet, multi-stage).
    (ii) Countershaft (e.g., single, double, triple).
    (iii) Continuously variable (e.g., pulley, magnetic, toroidal).
Note that GEM does not accommodate efficiency testing for continuously
variable transmissions.
    (4) Transmission oil sump configuration (conventional or dry).
    (d) You may subdivide a group of axles or powertrains with shared
attributes under paragraph (b) or (c) of this section into different
families.

Sec.  1037.235  Testing requirements for certification.

    This section describes the emission testing you must perform to
show compliance with respect to the greenhouse gas emission standards
in subpart B of this part, and to determine any input values from
Sec. Sec.  1037.515 and 1037.520 that involve measured quantities.
    (a) Select emission-data vehicles that represent production
vehicles and components for the vehicle family consistent with the
specifications in Sec. Sec.  1037.205(o), 1037.515, and 1037.520. Where
the test results will represent multiple vehicles or components with
different emission performance, use good engineering judgment to select
worst-case emission data vehicles or components. In the case of
powertrain testing under Sec.  1037.550, select a test engine and test
transmission by considering the whole range of vehicle models covered
by the powertrain family and the mix of duty cycles specified in Sec.
1037.510.
    (b) Test your emission-data vehicles (including emission-data
components) using the procedures and equipment specified in subpart F
of this part. Measure emissions (or other parameters, as applicable)
using the specified procedures.
    (c) We may perform confirmatory testing by measuring emissions (or
other parameters, as applicable) from any of your emission-data
vehicles.
    (1) We may decide to do the testing at your plant or any other
facility. If we do this, you must deliver the vehicle or component to a
test facility we designate. The vehicle or component you provide must
be in a configuration that is suitable for testing. For example,
vehicles must have the tires you used for testing, and tractors must be
set up with the trailer you used for testing. If we do the testing at
your plant, you must schedule it as soon as possible and make available
the instruments, personnel, and equipment we need (see paragraph (g) of
this section for provisions that apply specifically for testing a
tractor's aerodynamic performance).
    (2) If we measure emissions (or other parameters, as applicable)
from your vehicle or component, the results of that testing become the
official emission results for the vehicle or component. Note that
changing the official emission result does not necessarily require a
change in the declared modeling input value. Unless we later invalidate
these data, we may decide not to consider your data in determining if
your vehicle family meets applicable requirements.
    (3) Before we test one of your vehicles or components, we may set
its adjustable parameters to any point within the physically adjustable
ranges, if applicable.
    (4) Before we test one of your vehicles or components, we may
calibrate it within normal production tolerances for anything we do not
consider an adjustable parameter. For example, this would apply for a
vehicle parameter that is subject to production variability because it
is adjustable during production, but is not considered an adjustable
parameter (as defined in Sec.  1037.801) because it is permanently
sealed. For parameters that relate to a level of performance that is
itself subject to a specified range (such as maximum power output), we
will generally perform any calibration under this paragraph (c)(4) in a
way that keeps performance within the specified range. Note that this
paragraph (c)(4) does not allow us to test your vehicles in a condition
that would be unrepresentative of production vehicles.
    (d) You may ask to use carryover data for a vehicle or component
from a previous model year instead of doing new tests if the applicable
emission-data vehicle from the previous model year remains the
appropriate emission-data vehicle under paragraph (b) of this section.
    (e) We may require you to test a second vehicle or component of the
same configuration in addition to the vehicle or component tested under
paragraph (a) of this section.
    (f) If you use an alternate test procedure under 40 CFR 1065.10 and
later testing shows that such testing does not produce results that are
equivalent to the procedures specified in subpart F of this part, we
may reject data you generated using the alternate procedure.
    (g) We may perform testing to verify your aerodynamic drag area
values using any method specified in subpart F of this part. The
following additional provisions apply:
    (1) We intend to use the same aerodynamic test facility you used,
and if you provide any instruments you used, we intend to use those
instruments to perform our testing.
    (2) We may perform coastdown testing to verify your tractor drag
area for any certified configuration. If you use an alternate method
for determining aerodynamic drag area for tractors, we may perform
testing to verify Falt-aero as specified in subpart F of
this part.
    (3) We may test trailers (and devices receiving preliminary
approval) using the wind-tunnel method described in Sec.  1037.530. We
may also test using an

alternate method; however, we will determine how to appropriately
correct or correlate those results to testing with the wind-tunnel
method.
    (h) You may ask us to use analytically derived GEM inputs for
untested configurations as identified in subpart F of this part based
on interpolation of all relevant measured values for related
configurations, consistent with good engineering judgment. We may
establish specific approval criteria base on prevailing industry
practice. If we allow this, we may test any configurations. We may also
require you to test any configurations as part of a selective
enforcement audit.

Sec.  1037.241  Demonstrating compliance with exhaust emission
standards for greenhouse gas pollutants.

    (a) Compliance determinations for purposes of certification depend
on whether or not you participate in the ABT program in subpart H of
this part.
    (1) If none of your vehicle families generate or use emission
credits in a given model year,, each of your vehicle families is
considered in compliance with the CO2 emission standards in
Sec. Sec.  1037.105 through 1037.107 if all vehicle configurations in
the family have calculated or modeled CO2 emission rates
from Sec.  1037.515 or Sec.  1037.520 that are at or below the
applicable standards. A vehicle family is deemed not to comply if any
vehicle configuration in the family has a calculated or modeled
CO2 emission rate that is above the applicable standard.
    (2) If you generate or use emission credits with one or more
vehicle families in a given model year, your vehicle families within an
averaging set are considered in compliance with the CO2
emission standards in Sec. Sec.  1037.105 through 1037.107 if the sum
of positive and negative credits for all vehicle configurations in
those vehicle families lead to a zero balance or a positive balance of
credits, except as allowed bySec.  1037.745. Note that the FEL is
considered to be the applicable emission standard for an individual
configuration.
    (b) For non-box trailers and non-aero box vans, your vehicle family
is considered in compliance with the emission standards if all vehicle
configurations in that family meet specified design standards and have
TRRL values at or below the specified standard. Your family is deemed
not to comply for certification if any trailer does not meet specified
design standards or if any vehicle configuration in that family has a
measured TRRL value above the specified standard.
    (c) We may require you to provide an engineering analysis showing
that the performance of your emission controls will not deteriorate
during the useful life with proper maintenance. If we determine that
your emission controls are likely to deteriorate during the useful
life, we may require you to develop and apply deterioration factors
consistent with good engineering judgment. For example, you may need to
apply a deterioration factor to address deterioration of battery
performance for a hybrid electric vehicle. Where the highest useful
life emissions occur between the end of useful life and at the low-hour
test point, base deterioration factors for the vehicles on the
difference between (or ratio of) the point at which the highest
emissions occur and the low-hour test point.

Sec.  1037.243  Demonstrating compliance with evaporative emission
standards.

    (a) For purposes of certification, your vehicle family is
considered in compliance with the evaporative emission standards in
subpart B of this part if you prepare an engineering analysis showing
that your vehicles in the family will comply with applicable standards
throughout the useful life, and there are no test results from an
emission-data vehicle representing the family that exceed an emission
standard.
    (b) Your evaporative emission family is deemed not to comply if
your engineering analysis is not adequate to show that all the vehicles
in the family will comply with applicable emission standards throughout
the useful life, or if a test result from an emission-data vehicle
representing the family exceeds an emission standard.
    (c) To compare emission levels with emission standards, apply
deterioration factors to the measured emission levels. Establish an
additive deterioration factor based on an engineering analysis that
takes into account the expected aging from in-use vehicles.
    (d) Apply the deterioration factor to the official emission result,
as described in paragraph (c) of this section, then round the adjusted
figure to the same number of decimal places as the emission standard.
Compare the rounded emission levels to the emission standard for each
emission-data vehicle.
    (e) Your analysis to demonstrate compliance with emission standards
must take into account your design strategy for vehicles that require
testing. Specifically, vehicles above 14,000 pounds GVWR are presumed
to need the same technologies that are required for heavy-duty vehicles
at or below 14,000 pounds GVWR. Similarly, your analysis to establish a
deterioration factor must take into account your testing to establish
deterioration factors for smaller vehicles.

Sec.  1037.250  Reporting and recordkeeping.

    (a) Within 90 days after the end of the model year, send the
Designated Compliance Officer a report including the total U.S.-
directed production volume of vehicles you produced in each vehicle
family during the model year (based on information available at the
time of the report). Report by vehicle identification number and
vehicle configuration and identify the subfamily identifier. Report
uncertified vehicles sold to secondary vehicle manufacturers. We may
waive the reporting requirements of this paragraph (a) for small
manufacturers.
    (b) Organize and maintain the following records:
    (1) A copy of all applications and any summary information you send
us.
    (2) Any of the information we specify in Sec.  1037.205 that you
were not required to include in your application.
    (3) A detailed history of each emission-data vehicle (including
emission-related components), if applicable.
    (4) Production figures for each vehicle family divided by assembly
plant.
    (5) Keep a list of vehicle identification numbers for all the
vehicles you produce under each certificate of conformity. Also
identify the technologies that make up the certified configuration for
each vehicle you produce.
    (c) Keep required data from emission tests and all other
information specified in this section for eight years after we issue
your certificate. If you use the same emission data or other
information for a later model year, the eight-year period restarts with
each year that you continue to rely on the information.
    (d) Store these records in any format and on any media, as long as
you can promptly send us organized, written records in English if we
ask for them. You must keep these records readily available. We may
review them at any time.
    (e) If you fail to properly keep records or to promptly send us
information as required under this part, we may require that you submit
the information specified in this section after each calendar quarter,
and we may require that you routinely send us information that the
regulation requires you to submit only if we request it. If we find
that you are fraudulent or grossly negligent or otherwise act in bad
faith regarding information reporting and recordkeeping, we may require
that you

send us a detailed description of the certified configuration for each
vehicle before you produce it.

Sec.  1037.255  What decisions may EPA make regarding my certificate of
conformity?

    (a) If we determine your application is complete and shows that the
vehicle family meets all the requirements of this part and the Act, we
will issue a certificate of conformity for your vehicle family for that
model year. We may make the approval subject to additional conditions.
    (b) We may deny your application for certification if we determine
that your vehicle family fails to comply with emission standards or
other requirements of this part or the Clean Air Act. We will base our
decision on all available information. If we deny your application, we
will explain why in writing.
    (c) In addition, we may deny your application or suspend or revoke
your certificate if you do any of the following:
    (1) Refuse to comply with any testing or reporting requirements.
    (2) Submit false or incomplete information (paragraph (e) of this
section applies if this is fraudulent). This includes doing anything
after submission of your application to render any of the submitted
information false or incomplete.
    (3) Render any test data inaccurate.
    (4) Deny us from completing authorized activities (see 40 CFR
1068.20). This includes a failure to provide reasonable assistance.
    (5) Produce vehicles for importation into the United States at a
location where local law prohibits us from carrying out authorized
activities.
    (6) Fail to supply requested information or amend your application
to include all vehicles being produced.
    (7) Take any action that otherwise circumvents the intent of the
Act or this part, with respect to your vehicle family.
    (d) We may void the certificate of conformity for a vehicle family
if you fail to keep records, send reports, or give us information as
required under this part or the Act. Note that these are also
violations of 40 CFR 1068.101(a)(2).
    (e) We may void your certificate if we find that you intentionally
submitted false or incomplete information. This includes rendering
submitted information false or incomplete after submission.
    (f) If we deny your application or suspend, revoke, or void your
certificate, you may ask for a hearing (see Sec.  1037.820).

Subpart D--Testing Production Vehicles and Engines

Sec.  1037.301  Overview of measurements related to GEM inputs in a
selective enforcement audit.

    (a) We may require you to perform selective enforcement audits
under 40 CFR part 1068, subpart E, with respect to any GEM inputs in
your application for certification. Sections 1037.305 through 1037.315
describe how this applies uniquely in certain circumstances.
    (b) A selective enforcement audit for this part 1037 consists of
performing measurements with production vehicles relative to one or
more declared values for GEM inputs, and using those measured values in
place of your declared values to run GEM. Except as specified in this
subpart, the vehicle is considered passing if the new modeled emission
result is at or below the modeled emission result corresponding to the
declared GEM inputs. If you report an FEL for the vehicle configuration
before the audit, we will instead consider the vehicle passing if the
new cycle-weighted emission result matches or exceeds the efficiency
improvement is at or below the FEL.
    (c) We may audit your production components and your records to
confirm that physical parameters are correct, such as dimensional
accuracy and material selection. We may also audit your records to
confirm that you are properly documenting the certified configurations
of production vehicles.
    (d) Selective enforcement audit provisions for fuel maps apply to
engine manufacturers as specified in 40 CFR 1036.301. See Sec.
1037.315 for selective enforcement audit provisions applicable to
powertrain fuel maps.
    (e) We may suspend or revoke certificates based on the outcome of a
selective enforcement audit for any appropriate configurations within
one or more vehicle families.
    (f) We may apply selective enforcement audit provisions with
respect to off-cycle technologies, with any necessary modifications,
consistent with good engineering judgment.

Sec.  1037.305  Audit procedures for tractors--aerodynamic testing.

    To perform a selective enforcement audit with respect to drag area
for tractors, use the reference method specified in Sec.  1037.525; we
may instead require you to use the same method you used for
certification. The following provisions apply instead of 40 CFR
1068.420 for a selective enforcement audit with respect to drag area:
    (a) Determine whether or not a tractor fails to meet standards as
follows:
    (1) We will select a vehicle configuration for testing. Perform a
coastdown measurement with the vehicle in its production configuration
according to Sec.  1037.528. Instead of the process described in Sec.
1037.528(h)(12), determine your test result as described in this
paragraph (a). You must have an equal number of runs in each direction.
    (2) Measure a yaw curve for your test vehicle using your alternate
method according to Sec.  1037.525(b)(3). You do not need to test at
the coastdown effective. You may use a previously established yaw curve
from your certification testing if it is available.
    (3) Using this yaw curve, perform a regression using values of drag
area, CdAalt, and yaw angle, [psi]alt,
to determine the air-direction correction coefficients, a0,
a1, a2, a3, and a4, for the
following equation:
[GRAPHIC] [TIFF OMITTED] TR25OC16.083

    (4) Adjust the drag area value from each coastdown run,
CdArun, from the yaw angle of each run,
[psi]run, to 4.5[deg] to represent a wind-
averaged drag area value, CdAwa by applying Eq.
1037.305-1 as follows:

[GRAPHIC] [TIFF OMITTED] TR25OC16.084

    (5) Perform additional coastdown measurements until you reach a
pass or fail decision under this paragraph (a).
    (6) Calculate statistical values to characterize cumulative test
results at least once per day based on an equal number of coastdown
runs in each direction. Determine the wind-averaged drag area value for
the test CdAwa by averaging all
CdAwa-run values for all days of testing.
Determine the upper and lower bounds of the drag area value,
CdAwa-bounded, expressed to two decimal places,
using a confidence interval as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.085

Where:

CdAwa-boundeded = the upper bound,
CdAwa-upper, and lower bound,
CdAwa-lower, of the drag area value, where
CdAwa-upper is the larger number.
CdAwa = the average of all
CdAwa-run values.
    [sigma] = the standard deviation of all
CdArun values (see 40 CFR 1065.602(c)).
    n = the total number of coastdown runs.

    (7) Compliance is determined based on the values of
CdAwa-upper and CdAwa-lower
relative to the adjusted bin boundary. For purposes of this section,
the upper limit of a bin is expressed as the specified value plus 0.05
to account for rounding. For example, for a bin including values of
5.5-5.9 m\2\, being above the upper limit means exceeding 5.95. The
vehicle reaches a pass or fail decision relative to the adjusted bin
boundary based on one of the following criteria:
    (i) The vehicle passes if CdAwa-upper is less
than or equal to the upper limit of the bin to which you certified the
vehicle.
    (ii) The vehicle fails if CdAwa-lower is
greater than the upper limit of the bin to which you certified the
vehicle.
    (iii) The vehicle passes if you perform 100 coastdown runs and
CdAwa-upper is greater than and
CdAwa-lower is lower than the upper limit of the
bin to which you certified the vehicle.
    (iv) The vehicle fails if you choose to stop testing before
reaching a final determination under this paragraph (a)(7).
    (b) If you reach a pass decision on the first test vehicle, the
emission family passes the SEA and you may stop testing. If you reach a
fail decision on the first test vehicle, repeat the testing described
in paragraph (a) of this section for two additional vehicles of the
same configuration, or of a different configuration that we specify.
Continue testing two additional vehicles for each failing vehicle until
you reach a pass or fail decision for the family based on one of the
following criteria:
    (1) The emission family passes if at any point more than 50 percent
of the vehicles have reached a pass decision.
    (2) The emission family fails if six vehicles reach a fail
decision.
    (3) The emission family passes if you test 11 vehicles with five or
fewer vehicles reaching a fail decision.
    (4) The emission family fails if you choose to stop testing before
reaching a final determination under this paragraph (b).
    (c) We may suspend a certificate of conformity as described in 40
CFR 1068.430 if your emission family fails an SEA, subject to the
following provisions:
    (1) We may reinstate a suspended certificate if you revise
Falt-aero or make other changes to your testing methodology
to properly correlate your testing to the reference method specified in
Sec.  1037.525.
    (2) We may require you to apply any adjustments and corrections
determined under paragraph (c)(1) of this section to your other
emission families in any future application for certification.
    (d) If we test some of your vehicles in addition to your testing,
we may decide not to include your test results as official data for
those vehicles if there is substantial disagreement between your
testing and our testing. We will reinstate your data as valid if you
show us that we made an error and your data are correct. If we perform
testing, we may choose to stop testing after any number of tests and
not determine a failure.
    (e) If we rely on our test data instead of yours, we will notify
you in writing of our decision and the reasons we believe your facility
is not appropriate for doing the tests we require under this paragraph
(b). You may request in writing that we consider your test results from
the same facility for future testing if you show us that you have made
changes to resolve the problem.
    (f) We may allow you to perform additional replicate tests with a
given vehicle or to test additional vehicles, consistent with good
engineering judgment.
    (g) You must assign the appropriate CdA bin for your
compliance demonstration at the end of the model year for every
configuration you tested that failed under this section.

Sec.  1037.310  Audit procedures for trailers.

    (a) We may audit trailer manufacturers to ensure that trailers are
being produced to conform with the certificate of conformity. If this
involves aerodynamic measurements, we will specify how to adapt the
protocol described in Sec.  1037.305 to appropriately evaluate trailer
performance.
    (b) We may require device manufacturers that obtain preliminary
approval under Sec.  1037.211 to perform aerodynamic testing of
production samples of approved devices to ensure that the devices
conform to the approved configuration.

Sec.  1037.315  Audit procedures related to powertrain testing.

    (a) For vehicles certified based on powertrain testing as specified
in Sec.  1037.550, we may apply the selective enforcement audit
requirements to the powertrain. If engine manufacturers

perform the powertrain testing and include those results in their
certification under 40 CFR part 1036, they are responsible for
selective enforcement audits related to those results. Otherwise, the
certificate holder for the vehicle is responsible for the selective
enforcement audit.
    (b) The following provisions apply for a selective enforcement
audit with respect to powertrain testing:
    (1) A selective enforcement audit for powertrains would generally
consist of performing a test with the complete powertrain (engine and
transmission together). We may alternatively allow you to test the
engine on a dynamometer with no installed transmission as described in
Sec.  1037.551.
    (2) Recreate a set of test results for each of three separate
powertrains. Generate GEM results for each of the configurations that
are defined as the centers of each group of four points that define a
boundary of cycle work and average powertrain speed divided by average
vehicle speed, for each of the three selected powertrains. See 40 CFR
1036.301(b)(2) for an example on how these points are defined. Each
unique map for a given configuration with a particular powertrain
constitutes a separate test for purposes of evaluating whether the
vehicle family meets the pass-fail criteria under 40 CFR 1068.420. The
test result for a single test run in the audit is considered passing if
it is at or below the value selected as an input for GEM. Perform
testing with the same GEM configurations for additional powertrains as
needed to reach a pass-fail decision under 40 CFR 1068.240.

Sec.  1037.320  Audit procedures for axles and transmissions.

    Selective enforcement audit provisions apply for axles and
transmissions relative to the efficiency demonstrations of Sec. Sec.
1037.560 and 1037.565 as follows:
    (a) A selective enforcement audit for axles or transmissions would
consist of performing measurements with a production axle or
transmission to determine mean power loss values as declared for GEM
simulations, and running GEM over one or more applicable duty cycles
based on those measured values. The engine is considered passing for a
given configuration if the new modeled emission result for every
applicable duty cycle is at or below the modeled emission result
corresponding to the declared GEM inputs.
    (b) Run GEM for each applicable vehicle configuration identified in
40 CFR 1036.540. For axle testing, this may require omitting several
vehicle configurations based on selecting axle ratios that correspond
to the tested axle. The GEM result for each vehicle configuration
counts as a separate test for determining whether the family passes or
fails the audit. Select additional production axles or transmissions to
perform additional tests as needed.

Subpart E--In-Use Testing

Sec.  1037.401  General provisions.

    (a) We may perform in-use testing of any vehicle subject to the
standards of this part. For example, we may test vehicles to verify
drag areas or other GEM inputs as specified in paragraph (b) of this
section.
    (b) We may measure the drag area of a vehicle you produced after it
has been placed into service. We may use any of the procedures as
specified in Sec. Sec.  1037.525 through 1037.527 for measuring drag
area. Your vehicle conforms to the regulations of this part with
respect to aerodynamic performance if we measure its drag area to be at
or below the maximum drag area allowed for the bin to which that
configuration was certified.

Subpart F--Test and Modeling Procedures

Sec.  1037.501  General testing and modeling provisions.

    This subpart specifies how to perform emission testing and emission
modeling required elsewhere in this part.
    (a) Except as specified in subpart B of this part, you must
demonstrate that you meet emission standards using emission modeling as
described in Sec. Sec.  1037.515 and 1037.520. This modeling depends on
several measured values as described in this subpart F. You may use
fuel-mapping information from the engine manufacturer as described in
40 CFR 1036.535 and 1036.540, or you may use powertrain testing as
described in Sec.  1037.550.
    (b) Where exhaust emission testing is required, use equipment and
procedures as described in 40 CFR part 1065 and part 1066. Measure
emissions of all the exhaust constituents subject to emission standards
as specified in 40 CFR part 1065 and part 1066. Use the applicable duty
cycles specified in Sec.  1037.510.
    (c) See 40 CFR 86.101 and 86.1813 for measurement procedures that
apply for evaporative and refueling emissions.
    (d) Use the applicable fuels specified 40 CFR part 1065 to perform
valid tests.
    (1) For service accumulation, use the test fuel or any commercially
available fuel that is representative of the fuel that in-use vehicles
will use.
    (2) For diesel-fueled vehicles, use the appropriate diesel fuel
specified for emission testing. Unless we specify otherwise, the
appropriate diesel test fuel is ultra-low sulfur diesel fuel.
    (3) For gasoline-fueled vehicles, use the gasoline for ``general
testing'' as specified in 40 CFR 86.1305.
    (e) You may use special or alternate procedures as specified in 40
CFR 1065.10.
    (f) This subpart is addressed to you as a manufacturer, but it
applies equally to anyone who does testing for you, and to us when we
perform testing to determine if your vehicles meet emission standards.
    (g) Apply this paragraph (g) whenever we specify the use of
standard trailers. Unless otherwise specified, a tolerance of  2 inches applies for all nominal trailer dimensions.
    (1) The standard trailer for high-roof tractors must meet the
following criteria:
    (i) It is an unloaded two-axle dry van 53.0 feet long, 102 inches
wide, and 162 inches high (measured from the ground with the trailer
level).
    (ii) It has a king pin located with its center 36  0.5
inches from the front of the trailer and a minimized trailer gap (no
greater than 45 inches).
    (iii) It has a simple orthogonal shape with smooth surfaces and
nominally flush rivets. Except as specified in paragraph (g)(1)(v) of
this section, the standard trailer does not include any aerodynamic
features such as side fairings, rear fairings, or gap reducers. It may
have a scuff band no more than 0.13 inches thick.
    (iv) It includes dual 22.5 inch wheels, standard tandem axle,
standard mudflaps, and standard landing gear. The centerline of the
tandem axle assembly must be 145  5 inches from the rear of
the trailer. The landing gear must be installed in a conventional
configuration.
    (v) For the Phase 2 standards, include side skirts meeting the
specifications of this paragraph (g)(1)(v). The side skirts must be
mounted flush with both sides of the trailer. The skirts must be an
isosceles trapezoidal shape. Each skirt must have a height of 36  2 inches. The top edge of the skirt must be straight with a
length of 341  2 inches. The bottom edge of the skirt must
be straight with a length of 268  2 inches and have a
ground clearance of 8  2 inches through that full length.
The sides of the skirts must be straight. The rearmost point of the
skirts must be mounted 32  2 inches in front of the
centerline of the trailer tandem axle assembly. We may approve your
request to use a skirt with different dimensions if these

specified values are impractical or inappropriate for your test
trailer, and you propose alternative dimensions that provide an
equivalent or comparable degree of aerodynamic drag for your test
configuration.
    (2) The standard trailer for mid-roof tractors is an empty two-axle
tank trailer 42  1 feet long by 140 inches high and 102
inches wide.
    (i) It has a 40  1 feet long cylindrical tank with a
7000  7 gallon capacity, smooth surface, and rounded ends.
    (ii) The standard tank trailer does not include any aerodynamic
features such as side fairings, but does include a centered 20 inch
manhole, side-centered ladder, and lengthwise walkway. It includes dual
24.5 inch wheels.
    (3) The standard trailer for low-roof tractors is an unloaded two-
axle flatbed trailer 53  1 feet long and 102 inches wide.
    (i) The deck height is 60.0  0.5 inches in the front
and 55.0  0.5 inches in the rear. The standard trailer does
not include any aerodynamic features such as side fairings.
    (ii) It includes an air suspension and dual 22.5 inch wheels on
tandem axles.
    (h) Use a standard tractor for measuring aerodynamic drag of
trailers. Standard tractors must be certified at Bin III (or more
aerodynamic if a Bin III tractor is unavailable) for Phase 1 or Phase 2
under Sec.  1037.520(b)(1) or (3). The standard tractor for long
trailers is a Class 8 high-roof sleeper cab. The standard tractor for
short trailers is a Class 7 or Class 8 high-roof day cab with a 4 x 2
drive-axle configuration.

Sec.  1037.510  Duty-cycle exhaust testing.

    This section applies for powertrain testing, cycle-average engine
fuel mapping, certain off-cycle testing under Sec.  1037.610, and the
advanced-technology provisions of Sec.  1037.615.
    (a) Measure emissions by testing the vehicle on a chassis
dynamometer or the powertrain on a powertrain dynamometer with the
applicable duty cycles. Each duty cycle consists of a series of speed
commands over time--variable speeds for the transient test and constant
speeds for the highway cruise tests. None of these cycles include
vehicle starting or warmup.
    (1) Perform testing for Phase 1 vehicles as follows to generate
credits or adjustment factors for off-cycle or advanced technologies:
    (i) Transient cycle. The transient cycle is specified in Appendix I
of this part. Warm up the vehicle. Start the duty cycle within 30
seconds after concluding the preconditioning procedure. Start sampling
emissions at the start of the duty cycle.
    (ii) Cruise cycle. For the 55 mi/hr and 65 mi/hr highway cruise
cycles, warm up the vehicle at the test speed, then sample emissions
for 300 seconds while maintaining vehicle speed within 1.0
mi/hr of the speed setpoint; this speed tolerance applies instead of
the approach specified in 40 CFR 1066.425(b)(1) and (2).
    (2) For cycle-average engine fuel mapping under 40 CFR 1036.540 or
powertrain testing under Sec. Sec.  1037.550 or 1037.555, perform
testing as described in this paragraph (a)(2) to generate GEM inputs
for each simulated vehicle configuration, and for each of the four test
runs representing different idle speed settings. You may perform any
number of these test runs directly in succession once the engine or
powertrain is warmed up. If you interrupt the test sequence with a
break of up to 30 minutes, such as to perform analyzer calibration,
repeat operation over the previous duty cycle to precondition the
vehicle before restarting the test sequence. Perform testing as
follows:
    (i) Transient cycle. The transient cycle is specified in Appendix I
of this part. Initially warm up the engine or powertrain by operating
over one transient cycle. Within 60 seconds after concluding the warm
up cycle, start emission sampling while the vehicle operates over the
duty cycle.
    (ii) Highway cruise cycle. The grade portion of the route
corresponding to the 55 mi/hr and 65 mi/hr highway cruise cycles is
specified in Appendix IV of this part. Initially warm up the engine or
powertrain by operating it over the duty cycle. Within 60 seconds after
concluding the preconditioning cycle, start emission sampling while the
vehicle operates over the duty cycle, maintaining vehicle speed between
-1.0 mi/hr and 3.0 mi/hr of the speed setpoint; this speed tolerance
applies instead of the approach specified in 40 CFR 1066.425(b)(1) and
(2).
    (iii) Drive idle. Perform testing at a loaded idle condition for
Phase 2 vocational vehicles. Warm up the powertrain by operating it at
65 mi/hr for 600 seconds. Within 10 seconds after concluding the
preconditioning cycle, set the engine to operate at idle speed for 90
seconds, with the brake applied and the transmission in drive (or
clutch depressed for manual transmission), and sample emissions to
determine mean emission values (in g/s) over the last 30 seconds of
idling.
    (iv) Parked idle. Perform testing at an unloaded idle condition for
Phase 2 vocational vehicles. Warm up the powertrain by operating it at
65 mi/hr for 600 seconds. Within 60 seconds after concluding the
preconditioning cycle, set the engine to operate at idle speed for 600
seconds, with the transmission in park (or the transmission in neutral
with the parking brake applied for manual transmissions), and sample
emissions to determine mean emission values (in g/s) over the full 600
seconds of idling.
    (3) Where applicable, perform testing on a chassis dynamometer as
follows:
    (i) Transient cycle. The transient cycle is specified in Appendix I
of this part. Warm up the vehicle by operating over one transient
cycle. Within 60 seconds after concluding the warm up cycle, start
emission sampling and operate the vehicle over the duty cycle.
    (ii) Highway cruise cycle. The grade portion of the route
corresponding to the 55 mi/hr and 65 mi/hr highway cruise cycles is
specified in Appendix IV of this part. Warm up the vehicle by operating
it at the appropriate speed setpoint over the duty cycle. Within 60
seconds after concluding the preconditioning cycle, start emission
sampling and operate the vehicle over the duty cycle, maintaining
vehicle speed within 1.0 mi/hr of the speed setpoint; this
speed tolerance applies instead of the approach specified in 40 CFR
1066.425(b)(1) and (2).
    (b) Calculate the official emission result from the following
equation:

[GRAPHIC] [TIFF OMITTED] TR25OC16.086

Where:

eCO2comp = total composite mass of CO2
emissions in g/ton-mile, rounded to the nearest whole number for
vocational vehicles and to the first decimal place for tractors.
PL = the standard payload, in tons, as specified in Sec.  1037.705.
vmoving = mean composite weighted driven vehicle speed,
excluding idle operation, as shown in Table 1 of this section for
Phase 2 vocational vehicles. For other vehicles, let
vmoving = 1.