Im about to do a full service on vehicle. I was wondering about the front diff. the manual said to use 10w-40 oil, and a mech. said that I could use the gear and wetbrake oil which is used for the rear. What would you do? THANKs

 

I use the 10-40 and its never given me a reason to stop using it.
Strings

 

My friend is using the 10-40 and he never had any problems with it.