Working to freshen up my '85 F150 4X4, I'm now on to the transfer case and thought I was going to have to run for another drain pan! Old, dark thin stuff I'm happy to replace. The book says Mercon - but the stuff on my shelf is for an auto tranny. Still okay to use?

I'd like to use my hand pump in reverse to put fresh lube in the front differential and the book says GEAR OIL. Hmm... same stuff I put in the rear? It was the typical 80w-90 gear oil. The missing word in the manual is hypoid and I'd hate to use the wrong stuff. Thanks in advance for any help and sorry for being a pest.

 

I always used atf/mercon what ever I had or was the right price in my t-cases. Never had any issues.

 

Yes, most chain-driven transfer cases (like all '80-up Ford trucks) use ATF. Yes, the front diff uses the same oil as the rear diff. If either diff has a working limited slip, it needs the friction modifier additive. Follow the links on this page:

(click this text)

 

Thank you, Guys!