another driveshaft vibration thread...

[TheWipprSnappr]

So, at this point I feel like ive checked everything. 91 325i auto. has bad vibration at low speeds, 15-25 mph and worse at accel thru those speeds. no vibration, and drives perfectly smooth at highway speeds. Definitely feels like its in the driveline. All wheel bearings are good, trans crossmember is good, trans mounts are almost new, guibo is in great shape, CSB spins freely with no damage to rubber, just replaced spline clamp after old one was rotten (thought that would fix it but didn't). flanges on diff and trans are in good shape. Im stumped here . Not sure if the driveshaft needs to be balanced or not, I marked it before I took it apart. Hoping someone else has some experience here because im out of options other than getting it rebalanced, but before I spent the money on that I wanted to make sure.

[bmwman91]

Did you find the white marks that the factory made to show alignment of the halves?

[TheWipprSnappr]

no I didn't see any. the rear half was pretty scarred near the opening

[TobyB]

15-25 seems low for driveshaft...

t

[TheWipprSnappr]

15-25 seems low for driveshaft...

t

its probably closer to 25

[1843lamp]

So, at this point I feel like ive checked everything. 91 325i auto. has bad vibration at low speeds, 15-25 mph and worse at accel thru those speeds. no vibration, and drives perfectly smooth at highway speeds. Definitely feels like its in the driveline. All wheel bearings are good, trans crossmember is good, trans mounts are almost new, guibo is in great shape, CSB spins freely with no damage to rubber, just replaced spline clamp after old one was rotten (thought that would fix it but didn't). flanges on diff and trans are in good shape. Im stumped here . Not sure if the driveshaft needs to be balanced or not, I marked it before I took it apart. Hoping someone else has some experience here because im out of options other than getting it rebalanced, but before I spent the money on that I wanted to make sure.

Was this problem ever solved?I am having the same symptoms with my 87 auto transmission.

[jlevie]

The descriptions cited above suggest binding u-joints in the drive shaft. The fix is to replace the drive shaft with a quality rebuilt.

[1843lamp]

I dropped the rear exhaust ,heat shields and trans mount bracket ,no parts on the driveline system have ever been replaced ,they are all marked with the birthdate of my car ,the trans mounts looked cracked and very soft but they have no oil saturation on them .The csb looks dry and completely intact ,the two joints do not seem to have any play ,so I think the driveline will need to come completely out to check the u joints my car is and automatic with 100,000 original miles and there is no guibo ,only two u joints ,I was hoping to find broken trans mounts and or bad CSB.

[jlevie]

The drive shaft will have to be off the car to check the u-joints.

[TheWipprSnappr]

Actually I did fix the problem, sorry I sort of forgot about this thread. The preload on the CSB had never been set (pulling it forward in the tunnel, and tightening it) so under load, it was a bit off balance and was able to feel it that certain speed range. Hope that makes sense and hope it helps

EDIT: here is the thread for it http://www.r3vlimited.com/board/showthread.php?t=45943
some people don't experience issues with this, others do.

[1843lamp]

I bought a used rebuilt driveshaft today with greasable ,replaceable joints ,I was lucky to find one with three u joints and no guibo for an automatic transmission.It will be interesting to see what the existing problem is with the old driveshaft ,I am hoping it will be a bad u joint.