Shelf life of today's synthetic oil

Wet side WA
I've never seen or heard any problems due to oil being old, as long as it is stored in reasonable conditions with a tight lid and the oil meets the spec required for the motor. Pennzoil has been documented (photos) to have some additives precipitate and settle to the bottom of the bottle. Looks like dark sandy stuff but I've never seen it in person. I've had a bottle of PUP 5w30 in the garage for about a year but I shake it up every couple months along with my stash of gear oils and other fluids. So when someone talks about precipitation of additives, I always say shake it up and pour it in, the engine will cook it and mix it together just fine.
Yep right now I'm using about 6 or 7 year old Valvoline Synthetic got about 2900 miles on it and gee I can't tell the difference???????? :)


New York
I just filled my beater Hyundai with QS 'Synchron Ultra Premium' 5w30 synthetic made in 1998 (SJ version which the OM allows).
I used a NAPA Platinum filter. I have used SH rated Pennzoil Perfomax
which was even older than this QS in this vehicle before.
I certainly wouldn't worry about using oil that's just a few years old although I agree with storing it properly.

PS: There was no additive drop out visible and the clear bottle made that easy to see.
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