In Reply to: Re: Vibratio on speed over 55 posted by Wayne McKay on August 09, 2001 at 12:59:23:
Bruno Therrien 735i 1988
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.