I recently purchased a 2008 BMW X3 with 31k miles on it. Within a few days of owning it, the front shock started leaking. Although the car was no longer under warranty, the dealer took care of the problem and replaced the front shocks. So I pick up the car and start driving it home on the freeway. About 3 to 4 miles into the trip, the car starts shaking and vibrating. Thinking one of the wheels is loose, I pull over and inspect the car. No issues. No warning lights. Nothing. I limp the car back to the dealer. Upon closer inspection, it appears that the breaks are “pulsing” on/off causing the car to vibrate. The symptom becomes more obvious at 40mph+. When I finally get back to the dealer, the brake smell is very pronounced (I did not check which rotor/rotors got hot though). Now I'm thinking that during the shock replacement, someone messed up one of the wheel sensors. Once the ABS/traction control system got confused, it started pulsing the brakes. However, I would have expected some warning light. Since there is no light, I’m thinking it’s the ABS – note, however, that the pulsing was subtle enough where it could not be felt in the brake pedal itself. I get a call back from the dealer today and their diagnosis is “bad e-brake cable and rear rotors”. Certainly might explain the lack of warning lights but really, e-brake cable and rotors? The car had no break shimmying when braking and had great stopping performance before the shock service. How can the e-brake be pulsing the brakes even if the cable was bad? Any insight would be greatly appreciated. I usually do most of the work on my cars and this one makes no sense.