GM Service Manual Online
For 1990-2009 cars only
    • Inspect the brake pads every 9, 654 km (6,000 miles).
    • Inspect the brake pads any time that the wheels are removed (tire rotation, etc.).
    • Inspect both ends of the outer pad by looking in at each end of the caliper. The highest rate of wear normally occurs at these points.
    • Inspect the brake pad thickness on the inner pad in order to ensure that the brake pad has not worn prematurely. Some inboard brake pads have a thermal layer against the pad, integrally molded with the pad. Do not confuse this thermal layer with uneven inboard-outboard pad wear. View the inner brake pad through the inspection hole in the top of the caliper.
        Replace the disc brake pads whenever the thickness of any brake pad is worn to within 0.76 mm (0.030 in) of the pad. In the case of riveted brake pads, replace the pads when the pad wears to within 0.76 mm (0.030 in) of any rivet head. Replace disc brake pads in axle sets (front/rear) at the same time.