In Reply to: Re: Vibratio on speed over 55 posted by Rich on August 09, 2001 at 14:21:10:
I am also very interested in this problem. I have a 1988 735i w/ about 150K miles. My car shakes quite hard at 50-60 MPH only. I own a snap on balancer, and have balanced the wheels several times to no help. I was going to try and balance the wheels with the rotors installed as an assembly next. I do have a donor car with what looks like new front end stuff. When I apply the brakes during the shaking the problem seems to go away alittle.
Vibration (left/right on steering wheel) at that speed is typically due to the upper control (thrust) arm bushings, the tie rods and idler arm bushing in that order (assuming of course you have already eliminated the tires/wheels first). Vertical vibrations are also tire/wheel related followed by worn shocks.
My 91 750 is in th eshop checking on the oil leak (looks like hydraulic fluid but not sure) and steering wheel vibration on acceleration on speed about 55mph. Shop is called "Eurotech" here in MN ONLY dealing with Mercedes and BMW. Mechanic said usual suspect is driveshaft and wheel balancing issue for the vibration but not in my 750. He is doing a test drive and trying to find out. I will post what else can cause this symptom.
Oil leak is still under detect. Hydraulic fluid reservoir might be the cause pushing out the fluid but double check.