if your rears are wearing in on the inner side on a W140 its a good idea to check the camber struts in the rear suspension and also check the subframe mountings. Regarding the vibration, did you check the universal joint in the driveshaft for notchiness?

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)