Havoline 20w/20

[otis24]

In the utility room where I work, there is an unopened quart of Havoline 20w/20. It is rated SF, SE/CC. How old is this oil? What is it's purpose? How does a 20w/20 differ from a straight 20 weight?

 

[gregk24]

Wait what? Why isnt it just called 20 weight?

 

[Chris142]

Mid-late 70's. 20W20 was a popular weight back then.

 

[Shannow]

Still can do pretty good stuff...

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1174209

 

[gregk24]

Why is it called 20w20? What is different from that vs a 20 weight?

 

[Shannow]

http://intertek.ch/services/analytical-s...-nach-sae-j300/

Definitively meets the cold cranking and pumping stuff...

 

[datech]

You know that is a good question. I guess it is supposed to be equivalent to 20 weight when it's cold, and 20 weight when it is hot. Maybe there are additives that modify it to be a little different from plain 20 weight.

 

[Garak]

20w is measured differently than SAE 20. Shannow provided the link which gives the exact explanation.