Engine oil should be checked at least once a month, or at every fill-up. Check the level as well as the condition of the oil.

Checking the Oil Level

  1. Engine should be warm, and must be OFF.

  2. Open the hood and find the engine oil dipstick.

  3. Pull out the dipstick and wipe it off with a clean napkin.

  4. Reinsert the dipstick fully, and pull it back out.

  5. Read the oil level.

Dipstick styles may vary, but most have holes or a crosshatched area to mark full and low levels.

  • If the oil level is too low, the engine may get insufficient lubrication or overheat (oil is responsible for about 50% of engine cooling). This can result in engine damage.


  • If the oil level is too high, the oil may contact rotating engine parts and lead to oil aeration (oil and air mixing into a foam/froth). Aerated oil does not lubricate, cool, or pump through the engine as it should, which can result in damage similar to that on an oil-starved engine.


Checking engine oil.
9525829562_c58c5d6a19_b.jpg by highwaysagency. Licensed CC BY 2.0 via Flickr - https://www.flickr.com/photos/highwaysagency/9525829562

Oil Condition

  • Engine oil should be golden in color.

  • Dirty (dark or black) oil should be changed.

  • Oil that is “milky” (has the appearance of chocolate milk) is the result of coolant leaking into the oil. Have the vehicle serviced as soon as possible.

  • Small metal flakes in the oil are indicative of internal engine damage. These flakes will often have the appearance of very fine glitter.


Adding Oil
The low mark on a dipstick indicates the oil level is a quart low. If the oil level is low, be sure to add oil even if the vehicle will be getting an oil change soon. To add oil:


  1. Remove the oil cap.

  2. Using a funnel, add approximately a quart of oil.

  3. Give the oil a few seconds to drain down to the oil pan.

  4. Recheck the oil level.

  5. Repeat if necessary.

Add only the correct viscosity (5W-20, 10W-30, etc.) and type (synthetic, conventional, or semi-synthetic) of oil specified by the manufacturer. The type of oil you should use can be found in the owner's manual, or may be printed on the oil cap. 

Why do I have to use the correct viscosity oil?
The oil viscosity (such as 0W-20, for example) specified by the manufacturer is chosen by engineers based on several factors regarding the engine's design, with the clearances between moving parts being particularly influential. In order to lubricate the engine, oil must be able to flow between these moving parts.


  • Using oil that is too thick will result in insufficient lubrication, as the oil will not be able to get into the tight clearances meant for a thinner oil.

  • Using an oil that is too thin results in an oil film that's not thick enough to separate internal engine parts, also resulting in reduced lubrication.

Note that the same engine in the same model of vehicle may require a different weight of oil in different model years, so always check what is specified for the vehicle at hand.

Oil Viscosity and Engine Life
While using an incorrect viscosity oil in your vehicle isn't likely to cause immediate engine damage, it can shorten the life of your engine. Be sure to use only the oil specified for your vehicle. 


Get Your Vehicle Serviced if You Notice:

  • Excessive oil consumption or leaks

  • Blue smoke from the exhaust (burning oil)

  • A burning oil smell coming from the engine

  • Oil appears milky or has fine metal flakes in it