Options for replacing my whining 1987 325i manual trans rear diff?

[sdkfz232]

Aside from rebuilding the unit what options do I have? I have been searching for a used diff of the same model as mine but have been having no luck for quite awhile.

According to research, a 4.10 LSD will be able to bolt in without any modification? Do I need a certain year range or are all 4.10 LSDs compatible with my 1987 325i?

I have the patience and technical ability to rebuild the diff but I have not been able to find any good instructions as to how to rebuild these units, plus it seems it is most suggested to just ditch the old diffs and go with a 4.10LSD, am I wrong about that?

Thanks for the help, been doing a lot of research and hoping to clear this up via these questions.

[ArtFoodBMW]

I haven't found any good data on rebuilding an e30 diff. I believe the whining is usually caused by the pinion bearing(s) and I think they are relatively easy to replace...

I would recommend a 3.73 or 4.10 for an automatic 325i. All medium case 4.10's will be compatible with your car. A 4.10 from a 91 318is is not compatible due to its small case.

[TobyB]

Try looking at Metric Mechanic's site- they had a lot of diff info that might help you
put new bearings in.
And any earlier BMW manual will give you most of what you need-
the E21 manual had a lot of diff info in it, I seem to recall.

You need a new crush sleeve for the pinion, but if you just change bearings,
then the shimming probably won't change- the bearings aren't that expensive...
...but you need a press, some bluing to check it, etc.
Getting shims is a bit harder- look at RealOEM for part numbers, then hit Google.

hth

t