Originally Posted by foxy-stoat
The sensor is in constant contact with the brake PAD but doesn't squeak as its plastic.
Wrong. The sensor casing may be plastic, but the piece that rubs on the disc is some kind of graphite...and it does
squeak. I had serious squealing from the rear o/s/r brake. I rubbed the sensor end with emery and coated the rest of the sensor body with copper grease. Never heard another sound from the brakes since.