I started cleaning out the old barn which originally belonged to my great grandfather, today. I found an old can of oil, still full and unopened, despite the rusty top and bottom. He passed away in 1971 so I'm assuming the can is that old if not older. I was wondering if anyone can give an idea on the age of it. Its Esso Uniflo, made by Humble Oil and Refining Company. Humble Oil did alot of business in this area in the 60s and 70s. Anyhow on he back of the can it states "Oustanding year round heavy duty motor oil, for use under API services MI MM MS and DG in modern high compression gasoline engines. Uniflo 10W30 where SAE viscosity grades 10W-20W-20-30 are recommended". I think its a neat find, due to the fact I never knew my grandfather, heard nothing but good things about him, coincidentally I was born 20 years after his death on his birthday, so finding something from him was pretty neat.