Hummer H3. Manual — part 1677

1. Remove the oil pump suction hose from the oil pump screen.

2. Clean the hose and screen in cleaning solvent and air dry.

3. If the screen is embedded with debris, replace the screen.

4. Inspect the hose for cracking or tears.

5. Replace the hose if it is faulty.

6. Inspect the oil pump for free movement.

7. Replace the oil pump if there is any binding. Do not disassemble the oil pump. The oil pump

is serviced as a unit.

8. Inspect the wear clip on the oil pump.

9. Replace the oil pump if the wear clip is missing or faulty.

High/Low Range Components

Fig. 80: Annulus Gear
Courtesy of GENERAL MOTORS CORP.

1. Clean the ring gear in cleaning solvent and air dry.

2007 Hummer H3

2007 TRANSMISSION Transfer Case - BW 4493/4494 - H3

2. Inspect the ring gear teeth for the following conditions:

Damage or excessive wear

Chipped

Debris embedded in the root of the teeth

3. Replace the ring gear if it is faulty.

Fig. 81: Identifying High/Low Range Shift Sleeve Inspection Areas
Courtesy of GENERAL MOTORS CORP.

1. Clean the high/low range shift sleeve in cleaning solvent and air dry.

2. Inspect the high/low range shift sleeve for the following conditions:

Excessive wear or roughness on the shift fork pad surface (2)

Damaged, chipped or excessive wear on the engagement teeth (3)

2007 Hummer H3

2007 TRANSMISSION Transfer Case - BW 4493/4494 - H3

Excessive looseness or gouging on the mainshaft splines (1)

Fig. 82: High/Low Planetary Carrier
Courtesy of GENERAL MOTORS CORP.

1. Clean the high/low planetary carrier in cleaning solvent. Do not disassemble the planetary

carrier.

2. Air dry and ensure all cleaning solvent is removed from the bearings in the planetary gears

(1). Do not spin the planetary gears with compressed air.

3. Inspect the planetary gears for chipped teeth.

4. Inspect the planetary gears for debris embedded in the root of the teeth.

5. Inspect the planetary gears for excessive side movement from worn bearings, thrust washers

or shafts.

6. Inspect the low range teeth (2) for damage or excessive wear.

7. Inspect the high range teeth (3) for damage or excessive wear.

8. Inspect the input seal surface (4) for scoring or excessive wear.

9. Inspect the thrust bearing surface for scoring or excessive wear.

2007 Hummer H3

2007 TRANSMISSION Transfer Case - BW 4493/4494 - H3

10. Replace the high/low planetary carrier if any of the above conditions are found.

11. Inspect the mainshaft front support bearing for the following conditions:

Scoring

Pitting

Brinelling

Excessive wear

12. Replace the mainshaft front support bearing if it is faulty. Refer to Transfer Case

Disassemble and Transfer Case Assemble.

13. Inspect the high/low planetary thrust bearing for excessive wear or scoring.

14. Replace the thrust bearing if it is faulty.

Differential Components

2007 Hummer H3

2007 TRANSMISSION Transfer Case - BW 4493/4494 - H3