X3 vibration issue from rear

[spederman]

Ive got a 2007 X3 Auto tranny, that has a strange vibration from what feels like the rear of the car. It started at about 45K miles and ive had it at the dealership at least 4 times with no fix even after contacting BMW North america engineers. The dealer this far has tried an additive to the transmission oil, replaced the rear differential and replaced the transfer case.

I need some help to figure this out, so I'll try to describe the problem the best i can.

The vibration comes from the rear. You can feel it through out the car, the seats and steering wheel. It kinda feels like going over those rumble strips on the hwy with the rear tires , except not any where near as loud sounding as that. It will do it at any speed but the easiest way to repeat the vibrations is as follows: do about 60mph and hold it very steady, and then barely tap the gas pedal so it gives the rear end a little jerk to get moving/accelerating. It will vibrate for just a few seconds as long as you hold the gas pedal in that position. If you accelerate harder or decel it will stop. Another way it does the sound is everytime the rear wheels hit a sharp bump or pothole in the road. As soon as they do, it starts with the rumble/vibration for a few seconds, but if you hit accelerate/decel, it will stop the sound. The vibration only lasts a few seconds because as soon as you accel/decel it stops it.

So basically ive come to the conclusion it has something to do with giving the rear end area getting a sharp jolt of some sort, whether it be accelerate jolt by jabbing the gas pedal slightly or hitting bumps/potholes. other then this problem, the X3 runs like a champ, no shifting problems, no engine problems.

Anybody experience anything like this? Think it could possibly be the drive shaft being loose and getting knocked out of alignment when it hits something and then comes back into place ?

[JCL]

Your dealer seems to have tried a few things to find it. All the usual suspects.

It is always hard to diagnose over the internet, but I would be checking rear wheel bearings as well as the driveshaft. The driveshaft was off when the transfer case was done, so I wouldn't expect that it is loose (given that you had the problem before and after this work). If something is loose there it tends to remain out of balance, and not go back into alignment.

[Dr. C]

My 2004 3.0 is in the shop as I write for a similar complaint. I first noticed a vibration when accelerating through about 20 MPH but more recently it is most noticeable when accelerating from 60 to 70. Feel it through the steering wheel, accelerator pedal, etc. Vehicle has about 103k miles. The dealer first diagnosed the cause as the transfer case (found some shavings) but upon replacing it (not cheap), the vibration remained. They have now concluded that it's a worn/damaged drive shaft, which they recommend be replaced. Of course, the part needs to be shipped from Germany, so I'm in a holding pattern for another week or so. I can let you know whether a new drive shaft solves the issue when they get it in/installed.

[ZetaTre]

It is a vibration at a particular speed? If so the culprit is likely once of the u-joints in the driveshaft that failed. If the vibration increases with speed that is something else...

[pat7762]

anyone find out what the problem was? iam having the same issue was thinking TC but now after reading these post im think its not.

[Dr. C]

First, the dealer replaced the transfer case. About a $3200 tab. It didn't fix the problem. So the dealer removed the new transfer case and reinstalled my original one and kept looking. Turned out the vibration was coming from the drive shaft. New drive shaft fixed the problem, and the $ was less than half. Have a couple thousand miles on the repair and so far no more issues. Good luck with yours.