I have had car vibrations - not so strong in the sterring wheel but shaking at about 120 km/hr the whole car was shaking , the back of the passenger seat was moving significantly . After telling me that was due to
low tire profile (19 " rims) trying tire pressure adjustments , équilibrate the rims finally it appears that the tyres had a flat , after changing the tires everything was OK.
FYI i had conti tyres changed for bridgestone ( as i had on m'y E 90). Tyres were changed free of charge by the dealer.