
Originally Posted by
dr. d
engine oil is "stored" in the oil sump, which is the lowest part of the engine.
when the engine starts running, the oil pump pushes the oil to the rest of the engine, which is above the sump, to lubricate the engine.
when the engine is turned off, the oil is still in the upper parts of the engine. it takes a few minutes for that oil to gravitate down back to the sump.
in that period of gravitation, checking the oil level will give a misleadingly low reading.
oil expansion due to heat is very minimal. i doubt if one can see the difference, by just looking at the dipstick level. so, it does not matter whether you check oil level when hot or when cold. just give the oil a few minutes to gravitate back to the sump.
btw,
be sure the vehicle is level, when checking oil level.