After a few phone calls and internet search I found two PDF references:
Exxon has info that says 10 years (10 YEARS!!??) shelf life and the manufacture date is on the packaging?? Not sure what that means? would that be on individual cans, bottles, or on the cardboard bulk packaging??
Shell says 4 years with a retest period that could extend the self life and the same statement on where to find that date.
Any refined petroleum product could have issues and certainly the additives would with aging and settling. Avgas/mogas as well.
My initial concern was with all of the bulk oil out there but any size container should be suspect... Bottles, cans and drums are showing up on the internet and from your friends storage sheds so be careful if you are considering such.

We all have those friends that think they are helping out.
Inlet Petroleum in Anchorage said that Shell 15/50 (Black plastic bottle) has the self life embossed on the bottoms of theirs in ink of all things. (Black bottle/black ink)?? To be fair Shell does have white bottled product. I ran out to my shop for a look-see @ my 15/50 (Good luck)
If you have any doubts give it to Dick's tractor

I've got several bottles for him.
I guess the feds figure volume/churn takes care of it. NOT SO!!
The food industry is highly regulated to the point that bottled water has dates......
YES, Sometimes I have to much time on my hands.
