at 30k miles my pads were glazed over like ceramics but were about 50% worn. One of my rear pads had gotten so hot that the resin flowed out of solution with the pad and deposited on the surface, leaving only the friction media at the backing plate so upon removal of the caliper the pad crumbled apart.
I ground the ridge off the rotors, measured the thickness and found all of them to be at or near the wear limit stamped into the rotor hub. (Good thing I did the work myself or I'd be forced to buy new rotors as it is a CT state law that forbids a service center from releasing a viehicle with brakes worn beyond limits set by the manufacturer)
