The Stovebolt Site Forums The Shop Area General Truck Talk Just Wondering.

How long a shelf life does engine oil have??? Or does it last forever??? Which is a very long time.

Unopened it should last a very very long time. It's enemy is
oxygen. Most oil companies will tell you five years just to
cover their rear end.
Straight 10w is hard to find now a days, but I've got a bottle
of it that I use to fill oil cans. I've had it for about 40 years.
Still looks and acts like 10w oil when I pump it out of the
oil can. It does have a lid but so its been exposed to the
atmosphere, still it looks OK.
I would look for sediment settling to the bottom a cloudy look
to it or rancid smell before I would not use it in a Stovebolt.
It's my understanding that the additives tend to settle out of
a blended oil. So if it's a straight weight I'd say it good
for your life time.
Jerry should be along in the morning to give us the real skinny.

http://www.pbase.com/dennygraham/image/161854703/large
http://www.pbase.com/dennygraham/image/161854702/large
dg

I found a full case of old unused oil at my dad's house a few weeks ago, don't know the age of it but it could easily be well over 10 years. I put it in my 5.3 and am keeping a close eye on it. So far, so good. One of the factors to consider might be that today's oils are superior to the older stuff, but I figure that if it worked fine then, it should still be okay.

http://www.valvoline.com/auto-resources/motor-oil-faq

unopened motor oil should last a long time

I have a few cases of un opened "OLD" multi grade oil. When I use it, it seems to be cloudy at the end of pouring it out. I was wondering if the additives were settling out of it, and it wouldn't be safe using it.

Brian,

That is a good question. Are there any particulates?

Tim, there appeared to be some on the bottom of the container.

I think I would not use it in an engine.

I thought this line in you Valvoline link answered that question.
"If the rating is still current, we advise you shake the
container before use to blend any additives that may have
settled."

dg

Brian,

What is the brand and grade/rating of your "OLD" multi grade oil.

Also, try shaking the oil and then filter the oil. Look for particulates on the filter.

If I found particulates on the filter, I think I would not use the oil.

Pretty interesting guys, I always just assumed that little bit of milkiness was a bit of condensation or moisture of some kind, so I just stopped pouring a little early. Guess I was missing some of the good stuff!!! I'll have to try shaking the container next time.

If you poured the whole can into the engine, wouldn't the engine mix it back up as soon as you ran it?

Here ya go Tim.

Citgo---SL, SG
Citgo---SM, SL, GF3, GF4
Valvoline---SJ, SH, GF1 GF2
Exon--- SL, SJ, SH, SG, GF3
Quaker State---SM, GF3, GF4
BIG A---SJ, SH, GF1, GF2
NAPA--- SM, SL, GF1, GF2, GF3, GF4

Most likely the oil will mix OK, as long as there are no particulates that will not go back into "solution". There might be no particulates, unless something changed in the oil's composition while it was sitting/aging.

Brian,

All those oils have modern specs (and meet older specs).

By the way, are the GF* specs actually CF* specs?

http://www.oilspecifications.org/api_eolcs.php

Tim, went out to the garage this morning with my glasses and flash light. It reads GF on all the different brands.

OK, thanks, Brian,

Here is a better chart of oil grades:

http://www.upmpg.com/motor_oil_rate_gas.htm