i have a posi rear end (dont know the gears in it, my brother is looking that up for me) in my 86 z28, and i want to upgrade the oil in it to some royal purple. what weight should i use. also, there is the tag that says to used limited slip oil only. is there an oil specific for limited slips?

 

Royal Purple 75w-90 will do you good. I believe it has a LSD formula built in. If you need more LSD oil, your local parts store should be able to supply it.

 

http://www.royalpurple.com/prodsa/mgeara.html Yes it does have it built in.

 

thanks shnormo