Very bad vibration after clutch job

[handysmurf59]

I have done some searching, but could not find an exact answer to my problem. The clutch went out on my 325iC about a month ago. I replaced it with a kit from BavAuto. I also had the flywheel resurfaced at a local machine shop. I also decided to replace the trany and motor mounts at the same time since they were shot.
The clutch feels great now, but there is a very significant vibration starting at about 38MPH coming from just behind the transmission. You can feel it in the gear selector and the seats. The vibration started as soon as I put it back on the road. The flex coupling and CSB were newish and replaced by the PO. The U-joints also have no noticeable play when installed or removed.
What really makes this frustrating is that there was absolutely no vibration prior to the clutch. I followed the Bentley manual when doing the work and don't think it’s a problem with the reassembly. I am about at my whit's end with this problem. If any body got some ideas please let me know.

[jlevie]

When you pulled the transmission dir you separate the drive shaft sections? If so, when re-installing the drive shaft did you match up the paint marks? If the drive shaft halves aren't re-assembled in the excat original configuration it won't be in balance and can cause vibration.

[handysmurf59]

No I did not split the drive shaft during this job. The CSB was in good condition and so no work was required.
Does anyone have a picture of how the vibration dampener goes together at the back of the transmission? This is the only possible place that I think I could have gone wrong. The Bentley and www.realoem.com don't have a good picture.

[jlevie]

Any time I work on a car that has a vibration damper, it goes in the trash pile. So I can't be of much help in that regard.

[handysmurf59]

Any time I work on a car that has a vibration damper, it goes in the trash pile. So I can't be of much help in that regard.

Trashing the damper this morning. Will see what happens.

[red325i]

I've got the SAME vibration feel at 35-40 mph... I replaced the CSB and the flex disk last week...We marked the two halves before we pulled it apart to help with re-assembly... buuuut

One thing i noticed when i was putting it back together was that both halves of the drive shaft had white paint dots...and i noticed that they are NOT lined up-- but the paint marks that we made were..? Since im the third owner and I can validate that the CSB and flex disk have never been out before im not sure why those two paint marks were not lined up... (car only has 60K miles....so two PO would not have needed to do drive shaft stuff)

Only thing i can think is when it was coming apart i had some help and i dont know if it was pulled apart before we painted (maybe pulled out by accident and then put back in..misaligned)????

[red325i]

jlevie-- why do you remove the vibration damper??

[Bimmerista]

jlevie-- why do you remove the vibration damper??

Unnecessary weight

[jlevie]

jlevie-- why do you remove the vibration damper??

In my opinion, it is not necessary and when aged can cause vibration.

[handysmurf59]

Vibration dampner is in the dumpster and the problem is about 90% better. Don't know why it would have been a problem after I put it back together from the clutch and not before, but the vibration is mostly gone.