Hummer H2. Manual - part 1867

1. Place a straight edge across the engine block and front cover oil pan sealing surfaces. 

Avoid contact with the portion of the gasket that protrudes into the oil pan surface. 

2. Insert a feeler gauge between the front cover and the straight edge tool. The cover must be flush 

with the oil pan surface or no more than 0.5 mm (0.02 in) below flush.  

8. If the front cover-to-engine block oil pan surface alignment is not within specifications, repeat the cover 

alignment procedure.  

9. If the correct front cover-to-engine block alignment cannot be obtained, replace the front cover.  

CRANKSHAFT FRONT OIL SEAL INSTALLATION 

Tools Required 

J 41478 Crankshaft Front Oil Seal Installer. See Special Tools and Equipment .

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

  

Fig. 626: Crankshaft Front Oil Seal 
Courtesy of GENERAL MOTORS CORP. 

IMPORTANT:

z

Do not lubricate the oil seal sealing surface.  

z

Do not use the crankshaft front oil seal again. 

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

  

1. Lubricate the outer edge of the oil seal (140) with clean engine oil.  

2. Lubricate the front cover oil seal bore with clean engine oil. 

Fig. 627: View Of J 41478 
Courtesy of GENERAL MOTORS CORP. 

3. Install the crankshaft front oil seal onto the J 41478 guide. See Special Tools and Equipment .  

4. Install the J 41478 threaded rod, with nut, washer, guide, and oil seal, into the end of the crankshaft. See 

Special Tools and Equipment .  

5. Use the J 41478 in order to install the oil seal into the cover bore. See Special Tools and Equipment . 

1. Use a wrench and hold the hex on the installer bolt. 

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

  

2. Use a second wrench and rotate the installer nut clockwise until the seal bottoms in the cover bore.  

3. Remove the tool.  

4. Inspect the oil seal for proper installation. The oil seal should be installed evenly and completely 

into the front cover bore.  

OIL PAN INSTALLATION 

Fig. 628: Oil Pan Baffle & Bolts 
Courtesy of GENERAL MOTORS CORP. 

IMPORTANT:

z

The alignment of the structural oil pan is critical. The rear bolt hole 
locations of the oil pan provide mounting points for the transmission 
housing. To ensure the rigidity of the powertrain and correct 
transmission alignment, it is important that the rear of the block and 
the rear of the oil pan are flush or even. The rear of the oil pan must 
NEVER protrude beyond the engine block and transmission housing 

 

2004 Hummer H2 

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2