SAE 90 v 85/140

[Knuckle078]

Any significant difference ? Can I mix the 2 ?

 

[oldhp]

Mix them? Yes. Why? Leftovers? What is it for? More info please.

 

[Knuckle078]

2001 Mack dump truck with a new hogshead. I have always run 85/140 but the truck mechanic filled it with SAE 90

 

[zeng]

No problem in mixing the oils.
However in your intended truck application, I would say significant portions of SAE 90 is a no go for differential protection.

 

[Rob_Roy]

What does Mack recommend for your application?

No issue mixing, more of a question of if it is a suitable viscosity.