Hello, I have a 91' TII and I am a bit confused as to which oil to choose for my rear LSD diff. The manual states the grade is API GL-5 and the viscosity is SAE 90. Does that mean i can choose any gear oil with "x"W-90 with grade API GL-5? Could someone recommend a good diff. oil? Is it ok to use synthetic oil? Price is not a concern, i just want something good.

 

http://www.redlineoil.com/Products.aspx?pcid=7
I use this stuff.

 

Out of that list at redline, I'd use the lightweight shockproof.

IMHO, you should use a different oil in the trans and in the differential. In the differential you want a synthetic gear oil with the most advanced additive package possible. (Redline Lightweight Shockproof). In the transmission you want a GL-4 that is friendly to synchronizer action (Redline MT-90)

Dave

 

Ahhhh! ok. I understand now, thanks!