M3 Driveshaft rubbing after CSB/guibo replacement - What did I do?

[IronJoe]

I just got done replacing the center support bearing and guibo in my M3. After replacing these two parts the driveshaft does not spin freely - it rubs slightly in the rear (differential end). No amount of adjustment of the CSB fixes it.

More specifically, the tunnel is rubbing on a quarter sized patch of metal that appears to be welded onto the driveshaft. Not my picture, but you can see what I'm referring to:




Can anyone help me with this? Anyone else encounter this sort of problem?


Notes:
-I marked both halves of the driveshaft and reassembled correctly
-CSB is installed properly and preloaded
-Diff bushing does not look bad, but I bought a replacement anyway. Have yet to install.
-Could this be because the car is supported on jackstands under the rear subframes? I doubt it but I could be wrong.

[jlevie]

The piece of metal welded to the drive shaft is a balance weight. The only way I can see the drive shaft rubbing on the subframe would be if something was terribly misaligned. Since it wasn't rubbing before the guibo CSB replacement I'd be inclinded to suspect that the wrong CSB was used.

[IronJoe]

Well since my car is a very early '88, (05/1987 build date) I actually bought the wrong one (1988+) first.

The new early CSB (1984-1987) looks identical to the one I removed from the car.

[jlevie]

Did you purchase the M3 specific part (26112225620) or the 325e part? The part numbers are different so I'd guess that the parts are also.

[IronJoe]

I purchased the non-M3 part - all vendors list only one part number for the M3. Looks like I bought the wrong one again. And of course its three times the price.


Just found it on RealOEM. I will have to take it apart again and do some measuring tonight, but when I compared them the first time they looked identical.

[jlevie]

That would be the only thing that is obviously wrong and could explain the problem. Get the part that realoem calls for and then see if you still have a problem.