Unlike wine, motor oil doesn't improve with age.
Approximately how long will name brand multi-viscosity oil retain its lubricating and protective qualities when kept in the original sealed container?
TOM: Forever, but if I were you, I wouldn't keep it that long.
RAY: Unlike wine, motor oil doesn't improve with age. Moreover, the oil can't keep up with technological advances while its sitting in the can. My brother can--that's where he reads his Scientific American--but the oil can't.
TOM: Twenty-year-old oil is never going to be any better than it was twenty years ago. And oil technology has made great leaps in that time. So if you're using old oil, you're not getting the best lubrication and contaminant suspension available through today's technology.
RAY: I'm not sure why you're asking this question, Vic. If you've just uncovered a dusty two-year-old can of oil in your garage, go ahead and use it, I'm sure it's fine. On the other hand, if you've just inherited 50 cans of twenty-year-old oil, our advice would be to find 25 friends with lawnmowers and give them each two cans.