Hummer H2. Manual - part 1896

8. Lower the vehicle.  

9. Install the ignition coils. Refer to Ignition Coil(s) Replacement in Engine Controls - 4.8L, 5.3L and 

6.0L.  

EXHAUST MANIFOLD REPLACEMENT - RIGHT 

Tools Required 

J 43181 Heater Line Quick Connect Release Tool 

Removal Procedure 

 

2004 Hummer H2 

2004 ENGINE Engine Exhaust - Hummer H2

  

Fig. 7: Exhaust Manifold Pipe Nuts (Right) 
Courtesy of GENERAL MOTORS CORP. 

1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. 

2. Remove the exhaust manifold pipe nuts.  

3. Lower the vehicle.  

 

2004 Hummer H2 

2004 ENGINE Engine Exhaust - Hummer H2

  

4. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 

4.8L, 5.3L and 6.0L.  

5. Drain the coolant. Refer to Draining and Filling Cooling System in Engine Cooling.  

6. Using the J 43181 , remove the heater core hoses from the heater core. Position aside.  

7. Remove the spark plug wires. Refer to Spark Plug Wire Replacement in Engine Controls - 4.8L, 5.3L 

and 6.0L.  

8. Remove the oil level indicator tube. Refer to Oil Level Indicator and Tube Removal in Engine 

Mechanical - 4.8L, 5.3L and 6.0L. 

Fig. 8: Exhaust Manifold Bolts, Manifold & Manifold Gasket (Right) 
Courtesy of GENERAL MOTORS CORP. 

9. Remove the exhaust manifold bolts, manifold, and manifold gasket.  

10. Discard the gasket. 

 

2004 Hummer H2 

2004 ENGINE Engine Exhaust - Hummer H2

  

Fig. 9: Heat Shield Bolts, Heat Shield & Exhaust Manifold 
Courtesy of GENERAL MOTORS CORP. 

11. Remove the heat shield bolts (1), and shield (2) from the exhaust manifold (1).  

12. Clean and inspect the exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection in Engine 

Mechanical - 4.8L, 5.3L and 6.0L.  

Installation Procedure 

 

2004 Hummer H2 

2004 ENGINE Engine Exhaust - Hummer H2