[Diesel Dan]

I read an article from Blackstone labs where they used and then tested some oil that was 20+ years old! It still tested as good as new!

IIRC some of that stuff was more like 50 years old. There were no signs of age related deterioration.

 

[Diesel Dan]

Looked just fine...used it in the lawnmower, but wouldn't put it in my car

They tested the oil in the lab and it was just fine and one person is running it in his 1980s Chevy pickup.