GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC K Pickup - 4WD 🢒 Engine 🢒 Engine Cooling 🢒 Radiator Replacement

Removal Procedure
  1. Drain the coolant from the cooling system. Refer to Cooling System Draining and Filling .
  2. Remove the upper fan shroud. Refer to Fan Shroud Replacement .

    3. Object Number: 72748 Size: SH
  3. For the 5.0L and the 5.7L engines, remove the upper insulators and brackets.

    4. Object Number: 72749 Size: SH
  4. For the 6.5L and the 7.4L engines, remove the upper insulators and brackets.
  5. Disconnect the upper and lower radiator hoses.
    6. • For the 5.0L engine, refer to Radiator Hose Replacement .
    • For the 5.7L engine, refer to Radiator Hose Replacement .
    • For the 7.4L engine, refer to Radiator Hose Replacement .
    • For the 6.5L (Diesel), refer to Radiator Hose Replacement .
  6. Remove the transmission fluid cooler pipes. Refer to Transmission Replacement .
  7. Remove the engine oil cooler pipes. Refer to Engine Oil Cooler Hose/Pipe Replacement .
  8. Remove the lower fan shroud bolts and the lower fan shroud. Refer to Fan Shroud Replacement .
  9. Disconnect the coolant recovery reservoir/surge tank hose.
    10. • Refer to Coolant Recovery Reservoir Replacement .
    • For diesel engines, refer to Radiator Surge Tank Replacement .

    Object Number: 72748 Size: SH
  10. For the 5.0L and the 5.7L, remove the radiator from the lower insulators and brackets.

    11. Object Number: 72749 Size: SH
  11. For the 6.5L and the 7.4L, remove the radiator from the lower insulators and brackets.
  12. Inspect all of the parts and connections for leaks and wear.
  13. Replace the parts and/or connections, as necessary.

Installation Procedure

    Object Number: 72748 Size: SH
  1. For the 5.0L and the 5.7L engines, install the radiator on the lower insulators.

    2. Object Number: 72749 Size: SH
  2. For the 6.5L and the 7.4L engines, install the radiator on the lower insulators.
  3. Install the coolant recovery reservoir/surge tank hose.
    4. • Refer to Coolant Recovery Reservoir Replacement .
    • For diesel engines, refer to Radiator Surge Tank Replacement .

    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 lower fan shroud bolts and the lower fan shroud. Refer to Fan Shroud Replacement .

    5. Tighten
    Tighten the bolts to 9 N·m (71 lb in).

  5. Install the engine oil cooler pipes. Refer to Engine Oil Cooler Hose/Pipe Replacement .

    6. Tighten
    Tighten the fittings to 24 N·m (18 lb ft).

  6. Install the transmission fluid cooler pipes. Refer to Automatic Transmission.

    7. Tighten
    Tighten the fittings to 26 N·m (19 lb ft).

  7. Install the upper and lower radiator hoses.
    8. • For the 5.0L engine, refer to Radiator Hose Replacement .
    • For the 5.7L engine, refer to Radiator Hose Replacement .
    • For the 7.4L engine, refer to Radiator Hose Replacement .
    • For the 6.5L (Diesel), refer to Radiator Hose Replacement .

    Object Number: 72748 Size: SH
  8. For the 5.0L and the 5.7L engines, install the upper insulators.

    9. Object Number: 72749 Size: SH
  9. For the 6.5L and the 7.4L engines, install the upper insulators.
  10. Install the upper fan shroud and the upper fan shroud bolts. Refer to Fan Shroud Replacement .

    11. Tighten
    Tighten the bolts to 9 N·m (71 lb in).

  11. Refill the coolant in the cooling system. Refer to Cooling System Draining and Filling .
  12. Leak test on the cooling system. Refer to Cooling System Leak Testing .