I have a '98 M3/4 and my right front brake caliper seized up and was sticking off and on. This then heated rotor up excessively and warped it. Also caused car to pull to the right - I thought it was an alignment problem! HA! BMW replaced both front rotors, front brakes, and right side caliper. How could caliper go bad??!! Anyway, I did have to fight them on it - they finally gave in. This is just an FYI! Love the NEW brakes!