Just pulled my diff out today, to have the halfshaft seals and drive shaft seal replaced. Seems my buddy over tightened the top 4 bolts that hold the diff onto the carrier. Two snapped off, while trying to remove them. We brought the diff to a local shop, and they replaced all my seals and gaskets, with the BMW parts I supplied. The job cost $310.00.
Reality is, the job would have cost only about $110.00, the rest is the time to drill out the busted bolts. This time I put anti-seize on the bolts, and they went in hand tight till I needed to torque the last few turns.
I had my rear wheel bearings replaced at a cost of $500.00, because my buddy over tightened the hub nuts too tight. Both over tightening issues happened at the same time while doing the whole halfshaft/diff swap last year.
A very valuable lesson.
