So iIam digging thru my attached closed insulated garage this morning to put up my Christmas lights, and I walk by my years old stockpile of various Mobil 1 oils.

What i noticed surprised me.. The containers vary from maybe 4-7 years old. The 12+ containers have always been stored on one shelf since purchased, and of course never opened. I broke the plastic twist off cap seal to verify there was an intact internal seal, and you can see in the 15W-50 container on the left, its intact, there are no visible leaks, the 5qt plastic container has a some very slight moddled brown discoloration, and it has only a pint of liquid remaining, the shelf containing the oils is oil free. The other container pictured of 10W-40 has less then a qt missing. all the containers are partially collapsed.

I would not think these oils would essentially evaporate nor "leak" thru the plastic.

Anybody seen this before?


Is this something Mobil 1 might want to address?

There are no visible date/production codes apparent.

Makes me very concerned if what is left in the containers is safely usable.

Plastic is permeable, Steel not so much. If you plan decades long storage of a fluid don't plan on using plastic.

So a highly respected synthetic heavy weight motor oil on the market ,thought to be able to withstand high temps, compared to typical oils, almost completely evaporates in a handful of years at room temp?

Strangest thing I've ever seen. I have had quarts of oil around for years (not Mobil 1) but plastic quart size and haven't had that. Maybe something has changed with the material in the containers recently? Really weird. I wouldn't want to use the oil now.

Just think if it was a plastic 2-liter bottle of Pepsi probably be the same or less Pepsi in the bottle and FLAT as a piece of glass

Car and motorcycle plastic gas tanks have to meet permeation standards for the same reason your oil disappeared. The oil is somewhere but I think it's going to be tough to find it and put it back

Possible, low permeation gas "cans" were also part of a 2008 implemented EPA/CARB regulation so maybe they went after all petroleum containers?

Short of measuring the actual volume of oil still in the containers to verify that it's a full quart my guess is that the air in the top of the container leaked out some when there was a rise in room temperature and pressure built up when the temperature dropped the expanded air contracted and sucked in the sides of the container.

Kind of like how a plastic gas can does when it heats up on a 90 degree day and when the temperature drops back down at night the sides of the can suck in.

Why are you storing oil for 4 - 7 years? I can see a year or so.

You got the answer staring at you. What more needs saying?

Any oil that can eff up a plastic container like that is what's going in my engines, diffs, and hydraulics.

Exxon Mobil for the win.

i still have several pennzoil 50wt "racing" oil in the cardboard cans that are full.

Just curious ...... What ALTITUDE is the oil stored at ?

VERY Unusual "?" with NO sign of any leakage "?"

JCC, you will now test positive for MOBIL1. You are also pre lubed.

Zero indication of any leakage, not even the hint of any oily residue on exterior. elevation 14'.

I get the long term issue of permeability of gas storage in plastic, its well known, which is an ambient temp used product ( meaning elevated temps greatly increase the normal evaporation of any liquid), here we are talking 50W oil, intended to be used at temps approaching 300F, sold as a 15,000 mile interval high quality oil, so when is the last time someone checked a car stored for years (?) with the large oil surface in the oil pan/engine surfaces to see what has evaporated?

The containers picture here, have side vertical oil level indicators, the left one has 3/4" remaining, the right one is down about 1".

You say there is no evidence of leakage and they were still factory sealed.

Either it evaporated or it wasn't completely filled at the factory. One would assume that the one that had only 3/4" in it would have been noticed as being very light when you put it on the shelf. the one that was an inch down maybe not so much.

I just checked some old 13 year old royal purple I will end up putting in my lawn mower or something due to age and all are seemingly full.

It is a bit odd, but it is easy to break a seal on a jug or two if dropped at some point either before or after purchase.

Kinda odd oil evaporating though.

Sniper and Potato, yes valid points, I would never have bought a "short" fill, understand, there are 12? containers here, all show signs of collapsing and less then full, which is what first got my attention when they were sitting on the shelf. I only cracked the plastic cap seal on the one can, to verify the internal foil seal is as it should be, and it is.

If I would suspected that motor oil would/could evaporate, I never would have stockpiled oil, but I'm wondering is this just a synthetic oil issue, as I can't be the first person to witness any motor oil evaporating, but might be the first to stockpile synthetic oil in plastic containers for years to notice the condition, being synthetic is relatively new compared to dino oil, and its a bit more expensive investment, so less likely to be stockpiled.

Regardless, an expensive lesson learned.

I have some old dino oil in the shed my neighbor gave me, no idea how old it is but he died 7 years ago. It's still full, 7 plastic bottles, 1 qt each. Pennzoil 10w30 SG which was obsoleted in 2010.

Here is a good read, says 5 years on synthetic.

https://myengineneeds.com/does-synthetic-motor-oil-ever-expire/