Oil shelf life

Post by **FireFox31** » 25 May 2023, 01:47

I did two oil changes this week. The oil in one was bought 3.5 months ago, the other was bought 6 months ago. The 3.5 month old oil looked quite clear as I'd expect. The 6 month old oil looked much more brown as shown in the picture.

My Haynes manual says to change oil every six months (or 5k miles). Would the oil experience the same degradation if it sat new in the bottle for six months? If you use old oil, is its lifespan in the car that much shorter? What's the maximum age of oil you'd put in your car (if it were stored in a conditioned home)?

I've read that new oil has a shelf life, though a lot longer than six months. I once helped someone dispose of cases of unused oil because it was an unknown number of years old.

Maybe I'll change the oil in my third car with the oil I just bought. Then we'd see the color difference.

Post by **misha** » 25 May 2023, 02:12

Some brands says 3-5 years...some says 5-7 years...some of them like Motul says it's unlimited if bottle is sealed and unopened.

Post by **BlackBart** » 25 May 2023, 12:28

If you routinely oil your shelves, they will last forever.

Post by **abscate** » 25 May 2023, 15:02

Someone should send in one year old oil to Blackstone

WhatAmIDoing · Post by **WhatAmIDoing** » 25 May 2023, 15:09

If it's a sealed jug, then 5+ years easy on the shelf. If it's in the sun, maybe a year tops because the bottle will degrade. Always shake your jugs to ensure a homogeneous mixture before filling.

Post by **abscate** » 25 May 2023, 18:30

Last time I shook my jugs in a homogeneous place people put cash into my G string. Guitar didn’t play well with cash in it

Post by **scot850** » 25 May 2023, 20:42

Post by **Krons** » 25 May 2023, 22:16

Post by **amblerman** » 26 May 2023, 06:25

I find that different brands, "synthetic" vs blend vs "conventional" and viscosity all look a little different out of the bottle. Even different offerings from the same vendor can all look slightly different (Mobil 1 vs Mobil 1 Euro).

I routinely use oil that is several years old due to my habit of buying oil at steep discounts

Post by **wizechatmgr** » 26 May 2023, 06:34

Don't even get me started as to what constitutes synthetic in the USA vs Germany... Suffice it to say our standards are lower... I believe group 5 vs group 4 or such. Bobstheoilguy's forum likely has such details.

My guess would be synthetic should have a longer shelf life. That said, someone should contact Royal Purple and AMSOIL and see what their views are if really concerned.

Frankly, I've used oil that was 10+ years old in tractors and had no issue. Tractors get the heck beat out of them. I'm not sure I'd use canned oil from let's say the 70's at this point due to the changes in purity and additive packages, but I think anything from 2010 and newer is likely decent. I've used older jugs of Rotella & DELVAC without issues as well.

My guess would be it may break down a bit sooner, but if one is doing regular oil changes, the change interval for most vehicles is overkill anyways.