BMW Front and Chassis Vibration – Control Arm Bushings, Driveshaft? Most Models
This answer is applicable for many BMWs in addition to the one listed below.
car year: 2006
car model: 530i
I am getting a vibration in the front seats and to a lesser extent in the steering wheel at speeds of 65MPH +. I can actually look at the passenger seat and watch it shake even on a smooth road. I have had the wheels and tires balanced on a Hunter machine, so I don’t think that’s the problem. I have switched gears at those speeds and the vibration remains. Acceleration and deceleration don’t seem to impact it. At times I think I can hear a high pitched oscillating sound, but it’s impossible to pinpoint. It’s an automatic transmission. I appear to have pretty even tire wear. 69000 miles. It had a new transmission at 50000 miles. I would describe the vibration as the same feeling you get when braking with warped rotors, however, my braking still feels perfect. If I were to guess, I would be looking in the driveshaft/ Guibo/CV joints. Any other ideas? Thanks!
We would suggest that you may have worn front control arm bushings and/or ball joints or, as you have suggested, driveshaft issues. With these suggestions made, it would be more common for the vibration to be felt in the steering wheel more than the chassis floor (and seats) when the front control arms (bushings and ball joints) are worn. Add to this, the fact that while these issues are indeed common, your mileage is a bit low for problems with drive shaft parts (flex-disc, center bearing, U-joint and CV-joint). Additionally, you would usually experience a change in the vibration by varying the torque (acceleration vs. deceleration or mid-coasting), if it were driveshaft related …. but not always.
With the above thoughts considered, your mileage does fall into the early stages of control arm bushing wear. As the bushings age, they become softer and allow the control arms to move a bit more …. even though they look fine. We would suggest that you start by replacing the upper (or thrust) arm bushings if all else looks fine, by inspection (driveshaft parts, rear upper control arm bushings and rear lower/outer bushings .. also called ball-joints). If the vibration remains, we would look deeper into the driveshaft parts and the rear suspension bushing as noted above.