GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Engine 🢒 Engine Mechanical - 6.6L (LLY) 🢒 Valve Rocker Arm Cover Replacement - Upper Left Side

Removal Procedure
  1. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  2. Remove the air cleaner layer. Refer to Air Cleaner Replacement in Engine Controls.
  3. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  4. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  5. Remove the fuel injectors. Refer to Fuel Injector Replacement .

    6. Object Number: 1334380 Size: SH

    Important: After removing the charged air cooler duct, cover the turbocharger opening with tape in order to prevent entry of objects.

  6. Loosen the charged air cooler inlet duct connector to turbocharger clamp (1).

    7. Important: Do not use a screwdriver or other tool to pry the hose loose. The hose can be torn or damaged. Loosen the hose by twisting.

  7. Remove the charged air cooler inlet duct connector (4) from the turbocharger.
  8. Remove the battery cable to generator nut.
  9. If equipped, remove the auxiliary generator. Refer to Auxiliary Generator Replacement in Engine Electrical.
  10. Remove the battery cable harness clip from the bracket.
  11. Remove the battery cable junction block bolt from the power steering pump.
  12. Move and secure the battery cables out of the way.

    13. Object Number: 1378748 Size: SH
  13. Disconnect the fuel lines. Refer to Metal Collar Quick Connect Fitting Service in Engine Controls.
  14. Remove the fuel hose bracket nut.
  15. Remove the fuel filter/heater element housing. Refer to Fuel Filter Assembly Replacement in Engine Controls.

    16. Object Number: 674653 Size: SH
  16. Disconnect the main engine electrical harness connectors. Lift up on the latches in order to disconnect the connectors.
  17. Remove the main engine electrical harness from the clip on the bracket.

    18. Object Number: 1334921 Size: SH
  18. Disconnect the barometric pressure sensor electrical connector.

    19. Object Number: 1334916 Size: SH
  19. Remove the main engine electrical harness connector hold down bolts.

    20. Object Number: 1334948 Size: SH
  20. Remove the main electrical connector harness bracket bolts.
  21. Remove the main electrical connector harness bracket.
  22. Remove the water outlet tube. Refer to Water Outlet Tube Replacement in Engine Cooling.
  23. Remove the auxiliary generator, if equipped. Refer to Auxiliary Generator Replacement in Engine Electrical.

    24. Object Number: 1335454 Size: SH
  24. Reposition the left positive crankcase ventilation (PCV) hose clamp at the resonator tee.
  25. Remove the left PCV hose from the tee.

    26. Object Number: 1335462 Size: SH
  26. Remove the left PCV pipe bolt.
  27. Remove the left PCV pipe.

    28. Object Number: 1335635 Size: SH
  28. Remove the upper valve rocker arm cover bolts.
  29. Remove the upper valve rocker arm cover.
  30. Remove and discard the upper valve rocker arm cover gasket.
  31. If required, clean and inspect the upper valve rocker arm cover. Refer to Valve Rocker Arm Cover Cleaning and Inspection - Upper .

Installation Procedure
  1. Inspect the valve rocker arm cover gasket for damage. If the valve rocker arm cover gasket is not damaged, reuse the gasket.

    2. Object Number: 1335635 Size: SH
  2. Install the valve rocker arm cover gasket.
  3. Install the upper valve rocker arm cover.
  4. Install the upper valve rocker arm cover bolts.

    5. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 663904 Size: SH
  5. Tighten the upper valve rocker arm cover bolts in the sequence shown.

    6. Tighten
    Tighten the bolts to 8 N·m (71 lb in).

  6. Install the fuel injectors. Refer to Fuel Injector Replacement .

    7. Object Number: 1335462 Size: SH
  7. Install the left PCV pipe.
  8. Install the left PCV pipe bolt.

    9. Tighten
    Tighten the bolt to 18 N·m (13 lb ft).


    Object Number: 1335454 Size: SH
  9. Install the left PCV hose to the tee.
  10. Position the left PCV hose clamp at the resonator tee.
  11. Install the water outlet tube. Refer to Water Outlet Tube Replacement in Engine Cooling.
  12. Install the auxiliary generator, if equipped. Refer to Auxiliary Generator Replacement in Engine Electrical.

    13. Object Number: 1334948 Size: SH
  13. Install the main electrical connector harness bracket.
  14. Install the main electrical connector harness bracket bolts.

    15. Tighten
    Tighten the bolt to 21 N·m (15 lb ft).


    Object Number: 1334916 Size: SH
  15. Install the main engine electrical harness connector hold down bolts.

    16. Tighten
    Tighten the bolt to 10 N·m (89 lb in).


    Object Number: 1334921 Size: SH
  16. Connect the barometric pressure sensor electrical connector.

    17. Object Number: 674653 Size: SH
  17. Connect the main engine electrical harness connectors.
  18. Install the main engine electrical harness to the clip on the bracket.

    19. Object Number: 1378748 Size: SH
  19. Connect the fuel lines. Refer to Metal Collar Quick Connect Fitting Service in Engine Controls.
  20. Install the fuel hose bracket nut.

    21. Tighten
    Tighten the nut to 21 N·m (15 lb ft).

  21. Position the generator positive cable.
  22. Install the generator positive cable in the clip on the engine front cover.
  23. Install the generator positive cable and nut.

    24. Tighten
    Tighten the nut to 9 N·m (80 lb in).

  24. Install the fuel filter/heater element housing. Refer to Fuel Filter Assembly Replacement in Engine Controls.

    25. Object Number: 1334380 Size: SH
  25. Remove the tape from the turbocharger openings.

    26. Important: Lubricate the end of the duct prior to installation.

  26. Install the charged air cooler inlet duct connector (4) to the turbocharger.
  27. Tighten the charged air cooler inlet duct connector to turbocharger clamp (1).

    28. Tighten
    Tighten the clamp to 6 N·m (53 lb in).

  28. Install the air cleaner layer. Refer to Air Cleaner Replacement in Engine Controls - 6.6 (LLY).
  29. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  30. Fill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  31. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.