From what I've read, I think everyone who owns a BA has had this problem. Mine used to shake so bad I thought it would come apart at the seams. A new brake booster eventually solved the problem, but the quest for a vibration-free front end has seen me replace 2 sets of rotors, pads, all new front bushes, ball joints, added Boge struts, camber kit - and that's just the front. Drives better than a new one now...