The issue with the final drive isn't maintenance, it is improper assembly. If a given drive is thusly affected, it needs to be repaired and the damaged bearing replaced. Maintaining the improper preload will not help. Most dealers seem to just replace the bearing leaving the existing improper shims in place. This simply resets the clock until the new bearing fails from overload.good read on this thread. just bought my '02 (or is it '05, i'm not sure) this afternoon. will send to the shop for new tires and brakes. in one fell swoop will have them do complete maintenance on that drive, just to make sure !