Chevrolet Silverado / GMC Sierra. Service manual — part 1326

Fig. 24: Identifying Misalignment
Courtesy of GENERAL MOTORS CORP.

A misaligned outer race due to a foreign object. Clean the related parts. Replace the bearing.
Ensure the races are properly sealed.

Cracked Inner Race

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Front Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 25: Identifying Cracked Inner Race
Courtesy of GENERAL MOTORS CORP.

Cracked race due to improper fit, cocking, or poor bearing seats. Replace the bearing. Correct
bearing seats.

Fatigue Spalling

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Front Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 26: Inspecting Bearing Rollers & Races For Pitting, Grooves, Spalling & Excessive
Wear
Courtesy of GENERAL MOTORS CORP.

Flaked surface metal that results from fatigue. Replace the bearing. Clean all related parts.

Brinelling

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Front Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 27: Identifying Brinelling
Courtesy of GENERAL MOTORS CORP.

Surface indentations in the race way caused by the rollers under impact loading or caused from
vibration while the bearing is not rotating. Replace a rough or noisy bearing.

FOUR-WHEEL DRIVE DOES NOT ENGAGE

IMPORTANT: Before performing the following diagnostic procedure, ensure

that all electrical diagnostic procedures have been performed and
there are no DTCs.

Step

Action

Yes

No

Confirm operation of system. Refer to

2008 Chevrolet Silverado 1500

2008 Driveline/Axle Front Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado