When someone pisses you off enough that you threaten to stick something, like your foot, up their ass.
Dude, if you don't stop that shit, I'm going to check your oil.
by Oz in the ATL June 23, 2007
ramming your fingers up someone's ass
Hey, let's go check his oil!
by caesar December 09, 2003
A prostate exam.
I went to the doctor because my nards were sore and the SOB checked my oil.
by t June 29, 2004
When you run your finger across your bunghole in order to be certain that you wiped good enough.
I checked my oil and now I know how those stains got in my underwear.
by Bevis October 08, 2004