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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2000 🢒 Savana 🢒 Engine 🢒 Engine Cooling 🢒 Engine Coolant Thermostat Replacement

Engine Coolant Thermostat Replacement 4.3L

Removal Procedure

    Object Number: 160860 Size: SH
  1. Remove the air cleaner and the duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls.
  2. Partially drain the coolant. Refer to Cooling System Draining and Filling .
  3. Remove the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
  4. Disconnect the radiator hose from the thermostat housing.

    5. Object Number: 48323 Size: SH
  5. Remove the bolts attaching the thermostat housing to the thermostat.
  6. Remove the thermostat housing.
  7. Remove the thermostat.
  8. Clean the gasket mating surfaces.

Installation Procedure

Notice: When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.


    Object Number: 48323 Size: SH
  1. Install the thermostat.
  2. Install the thermostat housing to the intake manifold.
  3. Install the bolts to the housing.

    4. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).


    Object Number: 160860 Size: SH
  4. Connect the radiator hose to the thermostat housing.
  5. Install the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
  6. Install the air cleaner and the duct. Refer to Air Cleaner Assembly Replacement in Engine Controls.
  7. Refill the cooling system. Refer to Cooling System Draining and Filling .
  8. Bleed the air from the cooling system.
  9. Inspect the thermostat housing and the gasket for coolant leaks. Refer to Cooling System Leak Testing .

Engine Coolant Thermostat Replacement 5.0/5.7L

Removal Procedure

    Object Number: 160861 Size: SH
  1. Remove the air cleaner and the duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls.
  2. Partially drain the coolant. Refer to Cooling System Draining and Filling .
  3. Remove the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
  4. Disconnect the radiator hose from the thermostat housing.

    5. Object Number: 107496 Size: SH
  5. Remove the bolts attaching the thermostat housing to the thermostat.
  6. Remove the thermostat housing.

    7. Object Number: 347558 Size: SH
  7. Remove the thermostat.
  8. Clean the gasket mating surfaces.

Installation Procedure

Notice: When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.


    Object Number: 347558 Size: SH
  1. Install the thermostat.
  2. Install the thermostat housing to the intake manifold.

    3. Object Number: 107496 Size: SH
  3. Install the bolts to the housing.

    4. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).


    Object Number: 160861 Size: SH
  4. Connect the radiator hose to the thermostat housing.
  5. Install the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
  6. Install the air cleaner and the duct. Refer to Air Cleaner Assembly Replacement in Engine Controls.
  7. Refill the cooling system. Refer to Cooling System Draining and Filling .
  8. Bleed the air from the cooling system.
  9. Inspect the thermostat housing and the gasket for coolant leaks. Refer to Cooling System Leak Testing .

Engine Coolant Thermostat Replacement 7.4L

Removal Procedure

    Object Number: 160862 Size: SH
  1. Remove the air cleaner and the duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls.
  2. Drain the coolant. Refer to Cooling System Draining and Filling .
  3. Remove the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
  4. Disconnect the radiator hose from the thermostat housing.

    5. Object Number: 72728 Size: SH
  5. Remove the bolts attaching the thermostat housing to the thermostat.
  6. Remove the thermostat housing.
  7. Remove the thermostat.
  8. Clean the gasket mating surfaces.

Installation Procedure

Notice: When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.


    Object Number: 72728 Size: SH
  1. Install the thermostat.
  2. Install the thermostat housing to the intake manifold.
  3. Install the bolts to the housing.

    4. Tighten
    Tighten the bolts to 40 N·m (30 lb ft).


    Object Number: 160862 Size: SH
  4. Connect the radiator hose to the thermostat housing.
  5. Install the coolant recovery reservoir. Refer to Coolant Recovery Reservoir Replacement .
  6. Install the air cleaner and the duct. Refer to Air Cleaner Assembly Replacement in Engine Controls.
  7. Refill the cooling system. Refer to Cooling System Draining and Filling .
  8. Bleed the air from the cooling system.
  9. Inspect the thermostat housing and the gasket for coolant leaks. Refer to Cooling System Leak Testing .

Engine Coolant Thermostat Replacement 6.5L Diesel

Removal Procedure
  1. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim.

    2. Object Number: 160863 Size: SH
  2. Remove the air cleaner and the duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 6.5 (L65).
  3. Partially drain the coolant. Refer to Cooling System Draining and Filling .
  4. Remove the surge tank. Lay the surge tank aside. Refer to Surge Tank (Diesel) Replacement .
  5. Remove the transmission fill tube retaining nut and bolt. Remove the upper portion of the transmission fill tube.
  6. Remove the oil level indicator tube retaining nut. Remove the upper portion of the oil level indicator tube.
  7. Remove the upper radiator hose from the thermostat housing.
  8. Remove the engine harness connector retaining bolt from the bracket. Disconnect the connector and lay aside.
  9. Remove the fuel feed hose from the lift pump pressure test block. Plug the feed hose and position away from the thermostat housing bolts.

    10. Object Number: 344807 Size: SH
  10. Remove the bolts attaching the thermostat housing to the thermostat housing crossover.
  11. Remove the thermostat housing.
  12. Remove the thermostats.
  13. Clean the gasket mating surfaces.

Installation Procedure

Notice: When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.

Important: Thermostats must be replaced in pairs.


    Object Number: 344807 Size: SH
  1. Install the thermostats.

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

  2. Install the thermostat housing to the thermostat housing crossover.
  3. Install the bolts to the housing.

    4. Tighten
    Tighten the bolts to 42 N·m (31 lb ft).

  4. Connect the lift pump feed hose to the lift pump pressure test block.
  5. Reconnect the engine harness connector. Install the retaining bolt to the bracket.

    6. Tighten
    Tighten the bolt to 47 N·m (35 lb ft).

  6. Connect the upper radiator hose to the thermostat housing.
  7. Install the upper portion of the oil level indicator tube and retaining nut.

    8. Tighten
    Tighten the nut to 22 N·m (16 lb ft).

  8. Install the upper portion of the transmission fill tube. Install the retaining nut and bolt.

    9. Tighten

    1. Tighten the nut to 25 N·m (18 lb ft).
    2. Tighten the bolt to 47 N·m (35 lb ft).

    Object Number: 160863 Size: SH
  9. Install the surge tank. Refer to Surge Tank (Diesel) Replacement .
  10. Install the air cleaner and the duct. Refer to Air Cleaner Assembly Replacement in Engine Controls - 6.5 (L65).

    11. Important: In order to properly fill a system that has been completely drained, use the air bleed vents, located on the thermostat housing.

  11. Refill the cooling system. Refer to Cooling System Draining and Filling .
  12. Bleed the air from the cooling system.
  13. Inspect the thermostat housing and the gasket for coolant leaks. Refer to Cooling System Leak Testing .