Check the oil first thing in the morning.
How about settling a simple argument. Is it best to check the oil level when the car is cold, or after the car has been running?
RAY: Most owner's manuals tell you to check the oil first thing in the morning. Of course, if you do that, you have to be careful not to splash oil on your nightgown and slippers.
TOM: So we recommend you wait until after you get dressed and have breakfast. But the manuals are right. You do get your most accurate reading when the car is cold and on level ground.
RAY: Of course, one advantage of checking it while you're still in your nightgown is that flannel is very absorbant, and is great for wiping off the dipstick.