I get a vibration in the steering wheel at 65mph and it does not go away thereafter. In fact the vibration becomes more powerful (frequency appears to remain constant) with increasing velocity. I get the impression that the vibration is not a wheel balance issue since they were balanced only a few days ago. Furthermore, if the car is fully loaded the vibration sets in as early as 55mph.
At 70mph the vibration can also be felt under the seat. It is interesting to note that the rear driver side wheel bearing was replaced a 2 weeks ago by my dealer (MB shop). I did not have any real vibration in the rear of the car before then. Further when the car is fully loaded, the entire body shakes at 65mph+ to the point that it prevents me from driving at a greater velocity (because of sound and discomfort).
Any ideas ? could it be a steering shock ? would it cause the aboive described symptoms ? could the dealer have erred in his bearing installation ? what might he have done wrong or neglected ?
Any insights would be greatly appreciated !!!!!!!

Does the vibration get worse on accell/decell? or when turning the wheel?
Does it feel to be in the wheel or in the chassis (between the seats)?
I would have a tech look into it. The thing that comes to mind is a bad front flex disk or possibly a center drive shaft support and/or bearing. The possibilty still exists that you have lost a wheel weight.
Let us know what you find out about this problem.


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MB Medic
14 year MB tech
7 year shop foreman @ independent MB/Volvo shop

Could it be a engine problem?? My W140 used to have vibration when engine is hot. And when you hit the accelerator, it vibrates even more. And I took the car, and find out that couple of the cylinders are not firing. So, they just replace the connector for spark plugs/ignition wires. After, the car runs smoothly.

To start with what year & model is your car?? Different models have different types of problems! Since you state the problem started when the wheel bearing was replaced what were the symptoms that told you to have the bearing replaced? Possibly the wheel is loose?