GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC K Pickup - 4WD 🢒 Engine 🢒 Engine Electrical 🢒 Camshaft Timing Chain and Sprocket Replacement

Removal Procedure

    Object Number: 59872 Size: SH
  1. Disconnect both the battery negative cables from the batteries. Refer to Battery Cable in Engine Electrical.
  2. Rotate the engine to TDC.
  3. Remove the upper fan shroud from the radiator. Refer to Fan Shroud Replacement in Engine Cooling.
  4. Remove the drive belt from the water pump pulley. Refer to Drive Belt Replacement .
  5. Remove the lower fan shroud from the radiator. Refer to Fan Shroud Replacement in Engine Cooling.
  6. Remove the crankshaft balancer from the crankshaft. Refer to Crankshaft Balancer Replacement .
  7. Remove the water pump from the engine block. Refer to Water Pump Replacement in Engine Cooling.
  8. Remove the engine front cover from the engine block. Refer to Engine Front Cover Replacement .
  9. Remove the bolt from the timing chain sprocket to the camshaft.

    10. Object Number: 358425 Size: SH
  10. Remove the fuel injection pump drive gear from the camshaft.

    11. Object Number: 59876 Size: SH
  11. Remove the timing chain and sprocket from the camshaft.
  12. Replace the wood drift key if damaged. Refer to Timing Chain and Camshaft Sprocket Removal .

    13. Object Number: 59879 Size: SH
  13. Remove the sprocket from the crankshaft.

Installation Procedure

    Important: Make sure the timing marks are aligned.


    Object Number: 59879 Size: SH
  1. Install the crankshaft sprocket on the crankshaft.

    2. Object Number: 59876 Size: SH
  2. Install the camshaft sprocket with the timing chain to the engine block.

    3. Object Number: 358425 Size: SH
  3. Install the fuel injection pump drive gear to the camshaft.

    4. Object Number: 59872 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.

  4. Install the bolts from the timing chain sprocket to the camshaft.

    5. Tighten
    Tighten the bolts to 170 N·m (125 lb ft).

  5. Install the engine front cover to the engine block. Refer to Engine Front Cover Replacement .
  6. Install the water pump to the engine front cover. Refer to Water Pump Replacement in Engine Cooling.
  7. Install the crankshaft balancer to the crankshaft. Refer to Crankshaft Balancer Replacement .
  8. Install the lower fan shroud to the radiator. Refer to Fan Shroud Replacement in Engine Cooling.
  9. Install the drive belt on the drive pulleys. Refer to Drive Belt Replacement .
  10. Install the upper fan shroud to the radiator. Refer to Fan Shroud Replacement in Engine Cooling.
  11. Connect both the battery negative cables to the batteries. Refer to Battery Cable in Engine Electrical.
  12. Perform the TDC off set timing procedure. Refer to Fuel Injection Pump Top Dead Center Offset Adjustment in Engine Controls-6.5L.