I recently replaced both front wheel bearings on my 03 E39 525i - approximately 107k miles. Since replacement I get a "knock" when braking at low speed. Almost as if there was a hard spot in rotor or a stone embedded in a pad. The knock does NOT occur at speeds above 8 - 10 mph I double checked that the strut was aligned after the bearing replacement, I have double checked all mounting bolts. I have replaced the following trying to rectify: Caliper slide bushings and pins Rotors Pads It seems to be just the left front. There is NO high speed shimmy or shake and no issues when braking at speed. Any suggestions are welcome.
Brake pads can rock in the caliper and cause knocking at slow speeds. Anti-squeal pads may help if they keep the pads stuck to the caliper.
Rotor shield... Sometimes it can be as simple as a bent rotor shield, have you double checked yet? On my old 750iL, I had slightly bent one of the rotor shields and experienced a very similar occurrence...a low speed knocking when braking. Good luck!
