How long can fully synthetic oil be stored?

Well...it just dawned on me that I should use the 1.5 quarts in the old jug and then only 2.75 quarts from the new one so I don't have to worry about the oil getting old.

But still...how long can a synthetic oil lasts sitting on a shelf?

I don't think any type of oil "expires"

Kept sealed and in climate controlled conditions - pretty much Indefinitely. But practically - say 10 years.

Left opened - say one year until it is no longer good.

Kept sealed but not climate controlled, such as in your garage or shed, one year before use.

Tomko said:

Kept sealed but not climate controlled, such as in your garage or shed, one year before use.

Click to expand...

Unsealed, I can understand. But what's the problem with sealed/not climate controlled?

It's not kept in a stable environment. Constant heat cycling is similar to running it in an engine with constant heat cycling.

But you're free to test yourself to see how TBN declines from a sealed bottle kept in climate control for a year compared to one you've left in your garage.

According to the cases of Pennzoil Platinum full synthetic I have in the garage. The date of manufacturer is stamped on the box, along with a use by date 4 years after manufacturer.

I'm sure there's guys on BITOG (bob is the oil guy) that would say 10-20 years would be ok, but I'm not sure I'd store it that long!

I do shake the quarts before opening them though.

Don't seem to have this problem, 4 1/2 quarts go into my Cruze, other half a quart in my lawn mower or my snowthrower.

Also use synthetic in my other three vehicles, Supra, motorhome, and boat, use what's left over first than a new five quart container.

Think you answered your own question.

I know of some dino oil that has been stored for millions of years.

724 days

What a bunch of comedians. I knew I was in for it.

I read an article on BITOG about how they purchased 5 qts of 30 year old oil on EBAY, ran it for 5K in a vehicle and then ran all the normal tests on it. According to them it was still perfectly fine. I hope they are right! I got an unbelievable deal on the 5 quart jugs of Pennzoil Ultra, bought 23 jugs... I'll never need oil for my two vehicles again

Speaking of time, what is the time interval to change synthetic oil? 3 months for conv. oil right?

cruze01 said:

I read an article on BITOG about how they purchased 5 qts of 30 year old oil on EBAY, ran it for 5K in a vehicle and then ran all the normal tests on it. According to them it was still perfectly fine. I hope they are right! I got an unbelievable deal on the 5 quart jugs of Pennzoil Ultra, bought 23 jugs... I'll never need oil for my two vehicles again

Click to expand...

30 years ago we were still using SE grade oils. You can't run an SE grade oils today as it will foul your emissions equipment. It also won't last 5K. Maybe 3K - and only in a 30 year old engine designed to run SE oils.

Tomko said:

30 years ago we were still using SE grade oils. You can't run an SE grade oils today as it will foul your emissions equipment. It also won't last 5K. Maybe 3K - and only in a 30 year old engine designed to run SE oils.

Click to expand...

You are correct. Perhaps I should have been a little more specific, although I don't remember the exact details as it has been a few years ago they did not run it in a newer vehicle. I think it was an older model Chevy truck that one of the employee's owned. Anyway, the point of the article was that the oil was still good after all those years.

I'm still trying to figure out by what method oil will go bad on the shelf.

Volatile components (additives?) evaporating? I'd think they'll evaporate far faster in a hot engine.

Moisture getting into a open bottle? Blowby contains moisture. If you drive the car enough, the heat will drive it out. Now, that wouldn't be a good thing for someone who doesn't drive enough to "dry" the oil, but I'm not sure as motor oil is all that hygroscopic.

AutumnCruzeRS said:

Speaking of time, what is the time interval to change synthetic oil? 3 months for conv. oil right?

Click to expand...

1 year

cruze01 said:

I read an article on BITOG about how they purchased 5 qts of 30 year old oil on EBAY, ran it for 5K in a vehicle and then ran all the normal tests on it. According to them it was still perfectly fine. I hope they are right! I got an unbelievable deal on the 5 quart jugs of Pennzoil Ultra, bought 23 jugs... I'll never need oil for my two vehicles again

Click to expand...

BITOG guys also love using Blackstone Labs, which doesn't test for oxidation or nitration; two metrics that are relevant to that type of condition. An oil analysis report, and especially a Blackstone oil analysis report, will not be an accurate indicator of an oil's condition when degraded by long periods of storage.

That said, as long as it's sealed, it's fine. Once you take the cap off, the clock ticks much faster.

Hazlitt777 said:

What a bunch of comedians. I knew I was in for it.

Click to expand...

So did we!!! :mob: Anyhow....the consensus from the oil manufactures seems to be 5 years. Now whether I agree with that is another question as I'm sticking by my first response.