The 2008 Chevrolet Impala base model came with a 3.5-liter engine and an automatic transmission. The water pump is mounted on the right side of the engine and is driven by the accessory drive belt. When you replace the water pump, you will reuse its pulley on the new water pump. The 2008 Impala requires the use of DEXCOOL coolant, which cannot be mixed with any other type of coolant.
Park the vehicle on a level surface and set the parking brake. Lift the vehicle hood and support it with the hood prop rod. Allow the engine to cool completely before continuing the process.
Loosen the coolant pressure cap, and wait for the pressure to relieve. Remove the coolant pressure cap.
Lift the front of the vehicle into the air with the floor jack. Place the jack stand’s under the sub frame. Lower the floor jack until the vehicle rests securely on the jack stands. Remove the floor jack.
Place the drain pan under the radiator drain cock. Rotate the radiator drain cock until coolant begins to drain from the radiator. Once all the coolant has drained, tighten the drain cock.
Remove the drain pan from under the vehicle and store it in a safe location.
Remove the bolts securing the intake manifold cover to the intake manifold. Remove the intake manifold cover.
Loosen the water pump pulley bolts with the socket and ratchet. Draw out a sketch of the accessory belt routing on a piece of paper for later use.
Place the drive end of the 3/8-inch ratchet into the square hole on the belt tensioner. Rotate the belt tensioner clockwise. Remove the belt from around the tensioner pulley. Remove the belt from the engine.
Remove the water pump pulley bolts, and remove the pulley from the water pump.
Remove the bolts securing the water pump to the timing cover. Remove the water pump and water pump gasket from the timing cover. Clean the mating surface on the engine block with the wire brush.
Place the new water pump gasket onto the timing cover, followed by the water pump. Install the water pump mounting bolts. Tighten the water pump mounting bolts to 89 inch-pounds with the torque wrench.
Place the water pump pulley onto the water pump. Install the pulley bolts hand tight.
Inspect the accessory drive belt for any cracks, glazing or other damage. Route the accessory belt around the engine accessories. Hold tension on the belt at the belt tensioner. Rotate the tensioner clockwise, and slide the belt around the tensioner pulley. Slowly release the tensioner until tension is applied to the belt.
Tighten the water pump pulley bolts to 18 foot-pounds with the torque wrench.
Install the intake manifold cover onto the intake manifold. Tighten the intake manifold cover bolts with the socket and ratchet.
Lift the front of the vehicle off of the jack stands with the floor jack. Remove the jack stands from under the vehicle. Lower the vehicle to the ground.
Slowly fill the cooling system through the coolant pressure cap neck. When the coolant level stabilizes, continue the process.
Install the coolant pressure cap one turn. Start the engine, and hold the engine speed at 2,500 rpmfor 40 seconds. Shut the engine off. Remove the pressure cap and slowly fill the cooling system again until the coolant level is visible and stable.
Install the coolant pressure cap one turn. Start the engine, and hold the engine speed at 2,500 rpm for 30 seconds. Shut the engine off. Fill the cooling system until the level is visible and stable.
Install the coolant pressure cap one turn. Start the engine, and hold the engine speed at 2,500 rpm for 20 seconds. Shut the engine off. Remove the pressure cap and fill until the coolant level is visible and stable. Install the pressure cap tight.
Fill the coolant recovery bottle to the full line, and then add an additional 13.5 ounces of coolant. Close the coolant recovery lid. Shut the vehicle hood.
Take the used coolant to a local shop or part's store for disposal.
