Commutator End Frame & Bearing
WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1998 GMC Yukon, 1998 GMC Suburban, 1998 GMC Pickup, 1998 GMC Cab & Chassis, and 1998 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
Replace armature assembly if commutator outer diameter is less than 1.378" (36 mm) or if undercut depth is less than .008" (.2 mm). DO NOT undercut insulation. Ensure commutator end bearing has not spun in frame. If bearing has spun, replace frame and bearing. DO NOT lubricate bearing. If bearing is dry or damaged, replace bearing. Measure original bearing depth and install new bearing to same depth.