How to check oil in a car

To last longer, your engine must always have the proper level of oil. As you drive, some amount of oil is consumed and the oil level drops. As a result, the friction increases and the engine wears faster. By checking the oil level, you can catch if it’s getting low and top it up. You also can see how dirty your oil is and if it’s time for an oil change. First, check your owner’s manual, as it contains the proper instructions and safety precautions. Your engine needs to be warmed up and the car should be parked on a level spot. Here, we used the V6 Toyota Camry as an example.

Engine oil dipstick

1. Shut the engine off and set the handbrake. Wait for a couple minutes to allow the engine to cool down. Open the hood and locate the engine oil dipstick; in most newer cars it has a yellow handle that says ‘Engine Oil’. Your owner’s manual has a map of the engine compartment within the ‘Do-It-Yourself Maintenance’ section. The oil dipstick and the oil filler cap are marked on this map.

Checking engine oil

2. Pull the dipstick out. Be careful, some parts of the engine could still be hot. Hold the rag or towel under the lower end of the dipstick so the oil won’t drip onto the engine.

Checking engine oil

3. Wipe the dipstick out with a clean lint-free rag or paper towel.

Checking engine oil

4. Insert the dipstick back into the tube until it’s fully seated.

Engine oil level

5. Pull the dipstick out again and check the oil level. The dipstick has two marks that stand for “Low” and “Full.” The oil level should be between those marks.  In some cars, a dipstick has a cross section instead of marks; in this case, the level should be within the cross section. Once again, if in doubt, check your owner’s manual. After you’re done, make sure to put the dipstick back in its place.

How to read the oil dipstick. Examples:

Oil level on the dipstick

In this car, oil looks clean and the oil level is FULL.  Good job; keep driving.

Dirty oil in a car engine

Here, the level is okay, but oil looks dirty. It’s a good idea to have the oil change done soon.

Low oil level, dirty oil

This oil is very dirty and the level is below the LOW mark. It’s time to change your oil.

Low oil level in a car

This oil looks a bit dirty and the level is low. You may want to top it up. If it’s been a while since your last oil change, consider booking an appointment for your next oil change.

How to top up the oil level

Oil filler cap

To top up, use the same grade oil as you already have in the engine. The required oil grade (e.g. 5W-20, 0W-20 or 5W-30) is usually marked on the engine oil cap or you can find it in your owner’s manual. Make sure to use synthetic oil if the owner’s manual specifies so. In most cases, the owner’s manual has the reference how much oil needs to be added to bring the level from ‘Low’ to ‘Full’.

Adding oil to the car engine

For example, according to the owner’s manual, in this V6 Toyota Camry it takes 1.6 qt to bring the level from ‘Low’ to ‘Full’. Add a small amount, wait a minute to let it flow down, then recheck the level. If it’s still low, repeat; but don’t overfill. Use a funnel to avoid spills. Another option is to visit your dealer or repair shop and have them top up your oil for you.

Why does your engine need the proper level of oil?

The engine oil has two functions: it lubricates moving parts and helps dissipate the heat produced by combustion. The lubrication function is especially important. For example, the crankshaft, which is the engine main rotating part, makes on average 3.1 million revolutions per month of driving, yet it is only separated from the non-moving parts by a very thin layer of oil (around 0.0012 in or 0.03 mm) that is supplied under pressure. Oil also lubricates pistons moving up and down in the cylinders as well as all other moving parts of the engine.
By Testing Autos Editors.