Hummer H3. Manual — part 943

Fig. 8: Inspecting Bearing Rollers & Races For Heat Discoloration
Courtesy of GENERAL MOTORS CORP.

Surface depressions on the race and the rollers can be caused by hard particles of foreign matter.
Clean all the parts and the housings. Inspect the seals. Replace rough or noisy bearings.

Frettage

2007 Hummer H3

2007 Driveline/Axle Front Drive Axle - H3

Fig. 9: Identifying Frettage
Courtesy of GENERAL MOTORS CORP.

Corrosion can be caused by small relative movement of parts with no lubrication. Replace the
bearing. Clean the related parts. Inspect the seals. Inspect for proper lubrication.

Smears

2007 Hummer H3

2007 Driveline/Axle Front Drive Axle - H3

Fig. 10: Identifying Smears
Courtesy of GENERAL MOTORS CORP.

Smearing of the metal can be due to slippage. Slippage can be caused by the following factors:

Poor fits

Lubrication

Overheating

Overloads

Handling damage

2007 Hummer H3

2007 Driveline/Axle Front Drive Axle - H3

Replace the bearings. Clean the related parts. Inspect for proper fit and lubrication.

Stain Discoloration

Fig. 11: Identifying Stain Discoloration
Courtesy of GENERAL MOTORS CORP.

Discoloration ranges from light brown to black. This discoloration is caused from incorrect
lubrication or moisture. Reuse the bearing if you can remove the stains with light polishing. Reuse
the bearing if there is no evidence of overheating. Inspect the seals and the related parts for
damage.

Heat Discoloration

2007 Hummer H3

2007 Driveline/Axle Front Drive Axle - H3