Driving Your RV on Mountain Roads

Will your RV make it up the grade? Almost all grades, regardless of severity, will cause you to slow down. Any grade steeper than six percent is considered extreme and requires special attention. The steeper the grade or the longer the grade and/or the heavier the load, the more you will have to use lower gears to climb and descend mountains.

When going down steep grades, gravity will tend to speed you up. You must choose an appropriate safe speed, then use a low gear and enough braking power to hold you back without letting the brakes get too hot.

Slow the RV and shift the transmission to a low gear before starting down a grade.

Use the braking effect of the engine… by shifting to lower gears… as the principal way of controlling your speed. Save your brakes so you will be able to slow or stop as required by road and traffic conditions.

Remember: Never ‘ride’ the brakes by keeping your foot on the brake peddle. The use of brakes on a long and/or steep downgrade should only be a supplement to the engine braking.

Once the vehicle is in the proper low gear, the following is a proper braking technique:

  1. Apply the brakes just hard enough to feel a definite slowdown.
  2. When your speed has been reduced to approximately five mph below your “safe” speed, release the brakes. (This brake application should last for about three to four seconds.)
  3. When your speed has increased to your “safe” speed, repeat steps 1 and 2.

Do not drive in the fast lanes on a multiple-lane grade. Stay in the far right lane while climbing a steep grade if your motorhome or tow vehicle cannot maintain the legal speed limit.

It would be better to drop to a lower gear and slow down rather than attempt to pass slower vehicles and tie up the faster lanes if you don’t have enough power.


Share This Post

2 Responses to "Driving Your RV on Mountain Roads"

  1. While towing up a 6% grade my Chevolet 2500 (gasoline) engine usually has to down shift into 1st gear and run around 4,000 rpms. I attempt to feather the towing by lowering my speed during these extreme conditions.

    As expected, with the engive running at 3800-4000 rpm both it and the transmission starts to heat up as both are using the same transmission fluid. If I get reasonably close to the red line I pull over but leave the engine running so the engine fan continues to pull cool air through the radiator. I suspect turning off the engine is not the proper thing to do as the engine may heat even higher?

    My remedy should be to use a 3500 diesel PU or possible a 2500 diesel which provides more torch?

  2. Just a point of clarification. The engine and transmission do NOT use the same fluid.

    The engine uses typically 5W30 engine oil and the Chevy transmission requires Dexron IV.

    The transmission fluid is routed through a cooler which is part of the radiator, so it can contribute to engine overheating if it is being worked hard. In heavy duty towing applications there is usually also an air to oil auxiliary transmission cooler.

    Usually keeping the engine running at higher than normal RPM will help to more quickly get the temperature back down to a safe range.

    Yes, the 2500 or 3500 diesel will help out your towing situation.

Post Comment
