Hello All,

I recently did some major part replacement including:

New rear axles
New rear subframe mounts and trail arm bushings
New shocks
New sway bar links
New flex discs and Center bushing along with new guide bushings on the ends of driveshaft
New transmission mount
New rear diff mount
New motor mounts

After all was put back together the car mysteriously vibrates badly starting at around 42 mph.

I marked the driveshaft in the center and in relation to the rear diff and transmission, so that is not the issue.

I have tried loosening the Center carrier mount bolts and rolling the car to seat the shaft. That didn’t help.

I jacked up the rear and ran the car in drive and could hear the vibes start but couldn’t see any abnormal vibration looking under it, although the rear passenger side wheel did not turn as freely as the drivers side but I think that is a dragging brake caliper issue.

The vibrations occur in all the driving gears, but do not occur in park or neutral.

I’m pretty well stumped as to what to do next so I’d appreciate any fresh perspectives or similar experiences and general advise by the members.

Thanks in advance,

Marc
1981 w123 300D