Is there a top and bottom to the CSB

[Bmwdoubles_]

Update for me. Found a crack in my ARC-8’s. Put on new street tires on the stockies, had them road forced balanced, removed the dinan spacers and vibration gone. Thank god it wasn’t the drivetrain after my DIY repair. I thought maybe the CSB because I put the CSB on backwards and then was thinking is upside down. Def-check your wheel balance and then see if your vibration still exists. Road force balancing and tire indexing are the way for our sensitive little girls.

[RocketyMan]

Thank you for the update!

[drwankel]

Update on me as well. Put the old shaft back in, car is vibration free. Replaced the CSB on the old shaft while it was out. No preload for installation.

The easiest/most likely explanation is the aftermarket replacement shaft was not balanced correctly from the fabricator.

[a5m]

A little update of my own, just to keep this info consolidated for future benefit. Installed a Dorman Driveshaft (made my PTI; same manufacturer as Driveshaft Specialist) and I'm getting a vibration at ~50mph+. Can't believe all the effort for this.

Will do as drwankel and replace the CSB on the original and throw it back in. That one wasn't even really vibrating, just had the cowbell noise. Thought about just replacing CSB while I had it out, but wasn't sure how easy that would be and I needed to do all this in one day.

Anyway, no point in crying over spilled milk. Should be quicker second time around. Preloaded the CSB by like 2 or 3mm, just so the bolt is centered on the bracket. It was sitting quite a bit further back than the original. Will probably do the same second time around and hopefully be fine, or not preload at all depending on where the bracket lines up.

First pic is old, second is new.

[a5m]

Another update to close this out (with a follow up thread to warn people on these PTI driveshafts).

Replaced the CSB on the original driveshaft, greased the splines, and reinstalled it. No preload on the CSB since it was already naturally placed pretty far forward. No vibrations and smooth as glass. Cowbell noise gone.

Onto the Dorman (PTI) unit. U-Joint bolt had completely backed out. Not sure if this was due to the vibration, or the other way around. Also the CV Joint leaked leaving grease on the diff and on the threads of the new bolts. Probably due to it being overpacked. That was a fun hour and a half wasted cleaning everything. Maybe PTI was good at some point but their QC is practically non-existent based on my experience.

Replacing the original CSB was easier than I thought. Grabbed a 3 jaw puller set from Harbor Freight and It came right off. Pressing on the new one was easy with a large socket and a dead blow. Tapping it down one side at a time doesn't work. It needs equal pressure all around. Torquing the U-Joint bolt was interesting. Picked up this tool on Amazon that came in handy. Originally planned to just go with guddentight but seeing the Dorman's bolt backed out I'm glad I had ordered the tool and torqued it to spec.

Sorry again OP for detailing the thread. To answer the original question, there is a top and bottom to the CSB and it's marked on the OEM one. And the side of the bearing that protrudes out faces towards the front of the car. All the best to whoever takes this on. But stick to OE and just replace the CSB and guibo and be done with it.

[nleeumd]

Did you put the green fastener bolt from the driveshaft to the differential in the same spot? I have vibration over 60mph with new febi CSB but wasn’t specific with the counter weight green bolt

[nleeumd]

Just to follow up from my situation. The driveshaft issue has been resolved. I ended up removing the driveshaft and splitting the two halves and using a 3lb sledge hammer to make sure the CSB was seated properly. Upon installing, I also oriented the fasteners in the exact original orientation to the differnetial . The green bolt to the differential is lined up to the yellow dot/mark.
In addition, the center support bearing did not need any preload, the two bolts lined up to the right to the exact spot. I doubled checked my work and the car drives smooth! Hope this helps someone else in a similar situation.

[drwankel]

Originally Posted by a5m

Another update to close this out (with a follow up thread to warn people on these PTI driveshafts).

Replaced the CSB on the original driveshaft, greased the splines, and reinstalled it. No preload on the CSB since it was already naturally placed pretty far forward. No vibrations and smooth as glass. Cowbell noise gone.

Onto the Dorman (PTI) unit. U-Joint bolt had completely backed out. Not sure if this was due to the vibration, or the other way around. Also the CV Joint leaked leaving grease on the diff and on the threads of the new bolts. Probably due to it being overpacked. That was a fun hour and a half wasted cleaning everything. Maybe PTI was good at some point but their QC is practically non-existent based on my experience.

Replacing the original CSB was easier than I thought. Grabbed a 3 jaw puller set from Harbor Freight and It came right off. Pressing on the new one was easy with a large socket and a dead blow. Tapping it down one side at a time doesn't work. It needs equal pressure all around. Torquing the U-Joint bolt was interesting. Picked up this tool on Amazon that came in handy. Originally planned to just go with guddentight but seeing the Dorman's bolt backed out I'm glad I had ordered the tool and torqued it to spec.

Sorry again OP for detailing the thread. To answer the original question, there is a top and bottom to the CSB and it's marked on the OEM one. And the side of the bearing that protrudes out faces towards the front of the car. All the best to whoever takes this on. But stick to OE and just replace the CSB and guibo and be done with it.

Thanks for confirming that the PTI driveshaft is a POS. Steer clear folks.

[a5m]

Originally Posted by nleeumd

Did you put the green fastener bolt from the driveshaft to the differential in the same spot? I have vibration over 60mph with new febi CSB but wasn’t specific with the counter weight green bolt

Yes you have to put it at the same spot as before, or wherever the yellow mark is, since the entire drive line assembly is balanced together. Seems you got there by yourself! Such a PITA doing these jobs, let alone more than once.