How old is too old for oil

[davesl708]

Just remember, the oil you buy is a few hundred million years old already. As long as it is not contaminated it will last a few hundred years more.

 

[TomSeller]

Just remember, the oil you buy is a few hundred million years old already. As long as it is not contaminated it will last a few hundred years more.

However, the question remains as to whether Brontosaurus oil is better than Tyrannosaurus oil or if a blend is all you need.

I don't know that I trust the refining process to know that Tyrannosaurus Oil is in fact true Tyrannosaurus oil or if there is some Brontosaurus oil mixed in. Then of course, there is the discussion as to whether vegan derived Brontosaurus oil is better in the first place.

 

[OldMasterTech]

What does everyone do with unused but opened oil? Seems like I end up with odds and ends partial bottles from things like small engines that take less than a quart. I hate to just dump it in with the used oil for recycling but I don't have many needs for this oil.

I add unused clean oils to my home heating tank and use some for bar oil.

 

[DEWFPO]

I use years old oil all the time (I buy oil on sale in bulk, friends give me their old stock sometimes when they sell a vehicle), I just shake them up good before I pour them in. I've never had a single problem and I've been doing this since the 1970's.

DEWFPO

 

[SandburRanch]

If remembering to shake it presents a problem, store the containers/case upside down. At least in gets rotated when we open it and again when we pour it.

 

[DrRod]

If you have a lot of it you might look around for someone who heats with waste oil. There's a local garage that will take pretty much anything and run it through his heater. I had four 55 gallon drums of waste oil from the 60's. We used to use it to keep the dust down on a dirt road but times have changed. Plus there was probably lead in it given the era. So I hauled it down to the guy's garage and he was very pleased to have it.

 

[Opti-Mist]

The additive package can drop out of suspension as the oil ages. Most people look at the "black sludge" left in the bottom of an oil certainer when they do an oil change and think it's dirt from sloppy refining but..that's your oil additive, or part of them anyways.

Memory tells me that barium precipitates (with moisture contamination) as a black sludge.

 

[Copperhead]

I consider an oil too old when the spec it was made for does not meet the spec I need. i.e. I wouldn't put a CG diesel oil in a motor that required a CJ-4. In that case, the CG oil is too old. Come to think of it, I have a quart of Quaker State oil in the old metal can, unopened, sitting on a shelf in the shop. I know it is from circa mid 1970's. I ought to open it up and send a sample in to my oil sample lab and see if it is still good. My bet, it is. Won't get put in anything I run now anyway. Plastic containers, it might be another story.

 

[Sodo]

Sounds like a good time to change the oil in the lawnmower.

 

[woodchipper]

Old oil and surplus oil make for good "muti purpose" lubricant. Wether it be for garden tools, hinges from your barn, old fashioned pillow blocks, etc. Manual oilers are great containers to put them in.
If the can is sealed, and API classification is per specs, with the right viscosity, then I would not hesitate to pour it in my engine!(or whatever it's intended use).