[brettski]

Just wondering if there was a standard diff used on the 2000 E38 740iL, or if it was dependant upon how the car was ordered? I think mine is a Limited Slip Diff, but is there an easy way to confirm it one way or another, either by inspecting the diff, or from the VIN, etc?

Looking to change the diff oil, just to prolong its life (hopefully).

 

[brettski]

Quaife vs Wavetrack??

Well from the research that I have done, it looks like none of the BMW factory diffs used in the E38 were limited slip. Looking into what options there are to upgrade a diff to LSD comes back with the recommendation of either Quaife ATB Helical LSD (UK based) or Diffsonline using a Wavetrack carrier. The Quaife unit is gear driven and supposed to be really solid, where as the Wavetrack unit still uses friction plates.

Has anyone ever come across a Quaife diff, and is the cost of converting an open diff to an LSD version worththe time and money?

 

[witeshark]

I would think a replacement is far easier. Hopefully you can find one that matches your transmission gearing.