"old" oil question ?

Oldmanb777

Oldmanb777

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Oldmanb777
This has never been an issue for me, and I have no idea where to find the info. So I have several cases of oil sitting on my shelf. I used to buy it in larger amounts than I needed, to have it on hand. It was just easier since I got it from a wholesaler who gave me a better price when I bought more. So that said. I have several cases that have never been opened that I need to get rid of. I offered them to a friend who declined them as "they may be out of date". I have never heard of un opened oil being "out of date". new one on me, but as I thought about it, i have never considered it before. This oil was purchased about 15 yrs ago.
Any idea how to find a correct answer to that?
 
Oil doesn’t go bad by sitting on the shelf, as long as it hasn’t been exposed to extreme temperatures, but the additive package may become less effective over time. That being said, it’s understandable that someone wouldn’t want to purchase oil that’s been sitting on your shelf for 15yrs, especially when fresh oil is low cost and readily available.
 
Good question. 15 years is really old. I’ve got a few old qts lying around myself. Proly 5 yrs old. I tend to add one here and there to the fresh stuff when running low.
I’ve gotten many free qts of 5606 because of it being a few months out of date. Never had a problem with that or any other fluids that are slightly out of date, but 15 years would probably concern me.
 
Oil for plane, lawnmower, car??

The main thing for me is if the ‘spec’ was such that it didn’t rate for current application. For an auto that could be the ‘SJ’, ‘SN’, or ‘Dexos’, & whatever. I’d have no problem using older oil. As mentioned, there’s the lawnmower.

If not proper for any engine, it could always go in the squirt gun, lifetime supply.
 
Thanks for the links. I would have no problem using it myself in my own plane. But I have a problem giving it to someone else to use when i really don't have a perfectly reliable answer. It has never been out of the case, stored in my garage, etc. I wasn't selling it, just cleaning out some stuff, and need to have it gone.

It's Aeroshell 15W50

Looks like shell says it should be retested afer 4 yrs and every 2 yrs after that. So the answer is, i will dispose of it elsewhere.

Again thanks for that link, GRG55, very helpful.
 
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sourdough44 said:
The main thing for me is if the ‘spec’ was such that it didn’t rate for current application. For an auto that could be the ‘SJ’, ‘SN’, or ‘Dexos’, & whatever. I’d have no problem using older oil. As mentioned, there’s the lawnmower.
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I'll roll with this answer but with a caveat. If the oil was in sealed all plastic or all metal containers, I'd use it no problem. If this 15yr old oil is in the older style round cardboard with metal lids, I'd likely toss it.
 
The oil is fine. Give it away. If you're worried about the AeroShell 15w50 additive package, include a pint of CamGuard.
 
Plastic bottles still in the case. Cases have never been opened. The old round cardboard containers. I was given a motorcycle one from probably the mid 60's. It sits on the shelf collecting oily dust. I thought it was a pretty cool collector thing, but again, it needs to go away. Trying to downsize, and that's not working well.
 
Oldmanb777 said:
It's Aeroshell 15W50

Looks like shell says it should be retested afer 4 yrs and every 2 yrs after that. So the answer is, i will dispose of it elsewhere.
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I would also bet that it’s more of a liability issue for the manufacturers with aviation oils. The whole retest thing is another gimmick, because that would cost more than just buying a new qt.
 
Oldmanb777 said:
Looks like shell says it should be retested afer 4 yrs and every 2 yrs after that.
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FYI: the testing requirement is a mfg specification/standard requirement. Aircraft fuels and oils are part of the operating limitations of the type design/TC so they fall under certain rules. Fuels are more a pain to deal with when adherence to these standards/specifications is mandated.
 
The oil may be 15 years old but the engine is probably 30 years old that it's going in. Use the oil, add Camguard as has been said.
 
It's blended mineral and synthetic oils with additives. In my $40K+ engines? Pass. But heck, I'd pass on semi-synthetic if it was new yesterday. The guys that make it are on record with the answer. It'd make fine bar oil in a chainsaw, though.
 
I'm sure the oil is fine. But the mfg suggests otherwise (driven by sales and lawyers I'm sure), so I can't give it away to be used. I would have no problem using it myself, but letting somebody else use it, after knowing that the mfg recommends otherwise would be a no go for me.
 
Shell says it's fine. Sometimes some of the agents precipitate out, they say shake it back into solution if you like.
 
I have several cases of AeroShell 15W50 oil sitting on my shelf that have been there for about 15 years. I used to buy it in larger amounts than I needed, to have it on hand. It was just easier since I got it from a wholesaler who gave me a better price when I bought more.

The cases have never been opened. A friend suggested that, "They may be out of date." Is that a thing? Can unopened oil be "out of date?"
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The crude from which it's made is millions of years old, so what's another decade or two?
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That's a misapplied analogy. The oil in the ground, yes, was inherently stable in the absence of oxygen, and high temperature and pressure, for millions of years. However, the oil on your shelf has been removed from that environment and physically and chemically altered by the refining processes.

That said, the base oil and bright stock (the oily part) are pretty stable. The additive package perhaps not so much. The rule-of-thumb we used to use for non-critical applications was condition... if it was clear and bright (as opposed to hazy) and there were no particulates or precipitates, from additive breakdown, then we'd adjudge the oil fit for purpose. Paul

Here's Exxon's shelf-life table:

https://www.exxonmobil.com/aviation...s/aviation/greases/aviation_products_list.pdf

And Shell's equivalent:

https://www.embravo.com/wp-content/uploads/2015/01/RETESTING_Issue-6-Final-.pdf
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The STANAG cited is a NATO standard agreement. Paul

Blackstone Labs tested some really old (50+ year) automotive oil in the past. I believe their conclusion was that it didn’t matter. I can’t see aviation oil being different, just that you’re losing out on 15 years of oil technology advancing.
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Or avoiding some regression, in the case of the AeroShell 15W50 mentioned here. This oil is probably old enough that Shell was still using TCP (tricresylphosphate) to satisfy the Lycoming O320H2AD AD requirement. Shell has since shifted to TPP (triphenylphosphate) that is more corrosive to the rest of the engine. This could even be oil that came shortly after TPP introduction before extra copper corrosion inhibition was added. Safest use case is one quart of old oil per oil change... dilution is the solution to pollution! Paul

If you're worried about the AeroShell 15W50 additive package, include a pint of CamGuard.
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I think that makes sense. Paul

Shell says it's fine.
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Reference?

Sometimes, some of the agents precipitate out. They say shake it back into solution if you like.
Click to expand...
Reference?
 
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PaulMillner said:
That said, the base oil and bright stock (the oily part) are pretty stable. The additive package perhaps not so much.
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This. The oil stock is likely to last forever. However, additives like esters (TCP and the like) will gradually degrade depending on temperature and moisture content. Even plastic containers are not totally impermeable to water vapor. When esters hydrolyze they produce acids. How much? Hard to say. Depends on temperature, moisture, and time. A few years I personally would not spend much time worrying. 15 years is more uncertain.
 
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