GM Service Manual Online
For 1990-2009 cars only

Important: 

   • Inspect the toothed sensor rings for missing and/or damaged teeth. Missing and/or damaged teeth can result in erratic sensor signals.
   • Toothed sensor rings should show no evidence of contact with the rear axle wheel speed sensor. Determine the cause and correct if contact is evident.
   • Excessive runout of the sensor ring can cause erratic wheel speed sensor signals. Replace the rear drive axle if signs of runout are evident.

The rear axle speed sensor ring is an integral part of the rear drive axle. Replace the rear drive axle when replacing the sensor ring. Refer to Wheel Drive Shaft Replacement in Wheel Drive Shafts.