GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 GMC C Sierra - 2WD 🢒 Engine 🢒 Engine Controls - 6.6L (LB7) 🢒 Fuel Injection Fuel Rail Assembly Replacement - Bank 1

Removal Procedure

    Object Number: 674532 Size: SH
  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  3. Reposition the inlet hose clamps.
  4. Remove the inlet hose from the radiator.
  5. Remove the inlet hose from the water outlet tube.

    6. Object Number: 877281 Size: SH
  6. Remove the bolt attaching the positive battery cable junction box and bracket and move it out of the way.
  7. Loosen the charged air cooler inlet duct to turbocharger clamp (1).

    8. 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.

  8. Remove the charged air cooler inlet duct from the turbocharger.

    9. Object Number: 786978 Size: SH
  9. Disconnect the glow plug relay electrical connectors (1, 2, 3).
  10. Remove the glow plug bracket.

    11. Object Number: 674653 Size: SH
  11. Disconnect the engine wiring harness connectors.

    12. Lift up on the latch in order to disconnect the connectors.

  12. Remove the engine connector bracket and set aside.
  13. Disconnect the fuel in-line and return lines.
  14. Remove the L-bracket holding the fuel lines.

    15. Object Number: 687021 Size: SH
  15. Reposition the positive crankcase ventilation (PCV) hose clamp.
  16. Remove the PCV hose and move it out of the way.
  17. Remove the water pipe outlet from the thermostat housing.
  18. Remove the drive belt. Refer to Drive Belt Replacement in Engine Mechanical - 6.6L.

    19. Object Number: 652573 Size: SH
  19. Remove the air conditioning (A/C) compressor bolts and position aside.

    20. Object Number: 660448 Size: SH
  20. Remove the line from the junction block to the injection pump.

    21. Object Number: 660446 Size: SH
  21. Loosen the fuel return rear pipe (1) at the back end of the fuel rail and remove.

    22. Object Number: 660449 Size: SH
  22. Remove the fuel junction block.

    23. Object Number: 660451 Size: SH
  23. Remove the fuel injector feed pipe retainer bolts and retainers.
  24. Remove the fuel injector pipes.

    25. Object Number: 660456 Size: SH
  25. Remove the fuel rail bolts and rail.

Installation Procedure

    Object Number: 660456 Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the fuel rail and bolts.

    2. Tighten
    Tighten the bolts to 26 N·m (19 lb ft).


    Object Number: 660451 Size: SH
  2. Install the fuel injector feed pipes.

    3. Tighten
    Tighten the fittings to 41 N·m (30 lb ft).

  3. Install the fuel injector feed pipe retainers and bolts.

    4. Tighten
    Tighten the bolts to 4 N·m (35 lb in).


    Object Number: 660449 Size: SH
  4. Install the fuel junction block.

    5. Tighten
    Tighten the fittings to 25 N·m (18 lb ft).


    Object Number: 660446 Size: SH
  5. Connect the fuel return rear pipe (1) to the back end of the fuel rail.

    6. Tighten
    Tighten the fitting to 44 N·m (32 lb ft).


    Object Number: 660448 Size: SH
  6. Install the line from the junction block to the injection pump.

    7. Tighten
    Tighten the fitting to 40 N·m (30 lb ft).


    Object Number: 652573 Size: SH
  7. Install the A/C compressor bolts.

    8. Tighten
    Tighten the bolts to 50 N·m (37 lb ft).

  8. Install drive belt. Refer to Drive Belt Replacement in Engine Mechanical - 6.6L.
  9. Install the water outlet pipe to thermostat housing.

    10. Object Number: 687021 Size: SH
  10. Install the PCV hose.
  11. Reposition the PCV hose clamp.
  12. Install the L-bracket holding the fuel lines.
  13. Connect the fuel lines.
  14. Install the glow plug bracket.
  15. Install the glow plug relay. Refer to Glow Plug Relay Replacement .

    16. Object Number: 786978 Size: SH
  16. Connect the glow plug relay electrical connectors (1, 2, 3).

    17. Object Number: 877281 Size: SH
  17. Install the charged air cooler inlet duct to the turbocharger.
  18. Align the mark on the duct (2) with the mark on the turbocharger.
  19. Position the clamp (1) as shown for proper clearance.

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

  20. Install the bolt attaching the positive battery cable junction box and bracket.

    21. Object Number: 674532 Size: SH
  21. Install the inlet hose to the water outlet tube.
  22. Install the inlet hose to the radiator.
  23. Reposition the inlet hose clamps.
  24. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  25. Connect the negative battery cables. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  26. Replace all hold down ties.
  27. Start the engine and check for leaks or noises.
  28. After the engine warms up, refill the coolant reservoir to the proper level.