In Reply to: Limited slim diff. fluid... posted by Russ on July 31, 2001 at 04:46:53:
Necessary, yes, depending on mileage and type of oil.
Easy, don't know as I have a 535 but if it's similar then yes, it's very easy. Remove fill plug before drain plug. Have a pipe extension handy for the Allen wrench.
Fluid - Redline makes a gear oil for limited slip diffs., excellent stuff.