Well I've wrestled with the R&R of my driver's side rear bearing for 2 days now. The thing is mostly together now but when I tighten the stub axle bolt the hub locks up. When the bolt is loosened the hub turns nice and smooth. I cleaned the splines of both the axle and hub while everything was apart and they slide together pretty easily now so I don't think there is any binding there. After going over everything in my head ad-nauseum, the only thing that seems out of place is something that looks like a large washer. At some point while I was getting the old bearing out (it came out in about a bazillion pieces) this thing popped out on the floor.
So the 40 hour question is; is this a part of the old bearing or is it a spacer of some sort? If it's a spacer, where in the stack does it go? I've been on quite a few beemer forums and DIYs to get this done but none of them mention a spacer of any kind. Of course they don't mention pin drive hubs or bolts holding the stub axles either.