Three problems related to brake disc rotor have been reported for the 1997 GMC Sierra. The most recently reported issues are listed below.
Brakes felt spongy, took vehicle to dealer who noticed front rotors were disintegrating and had to be replaced.
Brake rotor separating from hub, causing excessive wear, vibrations; ultimately the wheel will fall off.
Consumer stated that anti lock brake came on 3-5 miles per hour and dealer had to replace both front hubs.