The oil should probably be checked after the car cools down for an hour or so, so that oil in the return galleries, cylinder head valleys, etc. is drained down so you don’t get a false reading. Locate the oil dipstick (use the owner’s manual). Hook a finger through the loop and pull the dipstick all the way out, releasing any clips that might be holding it in place. Use a paper towel or rag to wipe the dipstick clean so that you will have a clear reading. Insert the dipstick into its opening and push it firmly all the way back, as far in as it will go. Pull it out all the way, this time reading the oil level. When you are done, replace the dipstick in its opening.
- The dipstick has markings on it indicating a range for acceptable oil level (usually notched, dimpled, or scribed). Double check the markings you see against the owner’s manual. If the oil level is too low, appropriate motor oil must be added before the car can be driven. With a new car, take it to the dealer’s service or parts department; have them show you how to add oil, and buy the oil and funnel their mechanics use. With an older car, take it to an auto parts store; they will walk to your car, show you where to add oil, and recommend what to buy. Since some engines consume more oil than others, adding oil can also become a frequent task.
- Look at the color of your oil, too. Clean engine oil is a clear, golden color. Dirty engine oil is black or brown. If yours is dark, have a look at your car’s records to see when the oil was last changed. Darker engine oil can still run a car just fine, so go by the schedule more than by the color.
- You should also change engine oil according to both mileage and time. Consult your owner’s manual for the proper intervals. Even if you don’t drive the recommended number of miles, plan to change your oil about once every six months. Just sitting in the driveway, your car’s oil can break down and become less effective. Change your oil more frequently than the recommended schedule if your car gets severe use.
- Repeated, pronounced loss of engine oil can indicate a leak in a gasket or that your car is consuming oil. Keep a watchful eye in your driveway under where you park. Also look for signs of oil leaks on the outsides of the engine, and if you see any oil or consistently consume oil, take your car to a mechanic and explain what you have seen.
- If the oil looks milky or foamy, it may be contaminated with coolant, and should be checked by a mechanic. This condition could indicate a blown head gasket or other serious problems.