Sorry the question seemed so dumb! But I have heard that if a car sits for a long period of time,you should put fresh oil in.So,in theory,if you discover a car sitting in a barn for twenty years and want to restore it,you don't need to change the oil.Obviously I don't use my car that much.At the rate I'm going it would be about four years before a scheduled oil change.This is the dumbest (sorry) question I have EVER heard! Oil never goes bad. Its been sitting undergound for over 2000 years for goodness sake! It would only go bad after a LONG LONG time! By that I mean sitting in the engine for 30 years.