WARNING: This page is about a different car, the 2003 GMC Sonoma, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Fatigue Spalling
Courtesy of GENERAL MOTORS CORP.
Flaked surface metal that results from fatigue. Replace the bearing. Clean all related parts.