Same here. Had a vibration at the same speed. got new tires and was cured for a while but returned. mercedes shop said right control arms needed repacement .Replaced bushings and ball joints on both sides along with a tie rod. $1200 dollars later the vibration is worse. The tech said the wheels were out of round because I drove on the new tires too long. He said it might correct itself but I dont see how. One new tire coming this week. Hopefully this will cure the problem once and for all . The car as of now is unenjoyable to drive.