termostat replacement

6 CYL • FWD • AUTOMATIC
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GALLEGOS386
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how do i replace a termostat on a 2003 chevy impala?
Jan 17, 2011 at 1:16 PM
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BLUELIGHTNIN6
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3.4L (VIN E) Engine


1. Partially drain the cooling system.

2. Using hose clamp pliers, reposition the hose clamp at the thermostat housing. Disconnect the radiator hose from the thermostat housing.

3. Remove the exhaust crossover pipe using the following procedure:
1. Carefully remove the throttle body air duct.

2. Reposition the AIR pipe for access.

3. Remove the exhaust crossover heat shield bolts and remove the heat shield.

4. Remove the crossover bolts and lift the crossover from the engine.

5. Remove the thermostat housing bolts and remove the thermostat from the engine. Discard the gasket.


To install:

1. Clean all parts well. Make sure the sealing surfaces on both the thermostat housing gasket flange and the intake manifold are clean and free of corrosion damage. It is good practice to run a thread cutting tap or a clean bolt into the threaded holes in the manifold to clean out old sealer and dirt. The threads should be clean so the thermostat cover clamps the gasket evenly at assembly.

2. Position the thermostat in the intake manifold. Make sure it is seated.

3. Install the thermostat housing and bolts. Torque the bolts to 18 ft. lbs. (25 Nm).

4. Connect the hoses and reposition the clamps.

5. Install the exhaust crossover pipe. Torque the bolts to 18 ft. lbs. (25 Nm).

6. Install the exhaust crossover pipe heat shield and tighten the bolts to 89 inch lbs. (10 Nm).

7. Install the AIR pipe.

8. Install the throttle body air duct.

9. Refill the engine with the proper mix of DEX-COOL®and water. Check for leaks.



1. Partially drain the cooling system.

2. Using hose clamp pliers, reposition the hose clamp at the thermostat housing. Disconnect the radiator hose from the thermostat housing.

3. Remove the exhaust crossover pipe using the following procedure:
1. Carefully remove the throttle body air duct.

2. Reposition the AIR pipe for access.

3. Remove the exhaust crossover heat shield bolts and remove the heat shield.

4. Remove the crossover bolts and lift the crossover from the engine.

5. Remove the thermostat housing bolts and remove the thermostat from the engine. Discard the gasket.
Feb 9, 2011 at 7:20 AM
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