Honestly,
Impossible to have happened. I had a friend at BMW search the part using my Vin. My problem was my truck had the 1347mm and not the 1325mm driveshaft which made the pumpkin rare to come by. Also 4:10 gears which was verified using the Vin of the donor. It is identical down to the numbers. (Already thought of that). Do the rear diffs in the x5 have clutches (I don't think so, all that is controlled via transfer case)