Where Is the Thermostat on a 2004 Olds Silhouette?

The thermostat for the 2004 Oldsmobile Silhouette is located at the front of the engine. In order to replace the thermostat it will be necessary to remove the exhaust crossover pipe and the air intake tube. No special tools are required; however, RTV silicone sealer will be needed to help prevent leaks at the thermostat housing. The 2004 Silhouette uses DEXCOOL coolant,which is designed to last up to 5 years or 150,000 miles. This is the only coolant acceptable for use in the Silhouette's cooling system.

Instructions

Allow the engine to cool completely. Set the parking brake. Lift the vehicle hood and support it with the hood prop rod.

Put on safety glasses. Lift the front of the vehicle into the air with a floor jack. Place jack stands under the front frame rails of the vehicle, then lower the floor jack until the car is resting securely on the jack stands. Remove the floor jack.

Locate the coolant drain bolt, located on the passenger side of the engine block below the passenger side motor mount. Place a drain pan under the coolant drain bolt. Loosen the drain bolt with a socket and ratchet until coolant begins to drain from the engine. Allow two quarts of engine coolant to drain. Tighten the coolant drain bolt to 16 foot-pounds of torque with the torque wrench.

Remove the drain pan from under the vehicle and store it in a safe place away from children and animals. Lift the vehicle off of the jack stands with the floor jack and remove the jack stands from under the vehicle. Lower the vehicle to the ground.

Loosen the clamps for the air intake tube with a screwdriver. Disconnect the Mass Airflow sensor electrical connector by squeezing on the tab and pulling it away from the sensor. Pull the intake tube off of the intake manifold and the air cleaner box.

Remove the three nuts securing the exhaust crossover pipe to the front exhaust manifold and the rear down pipe with the socket and ratchet. Remove the exhaust crossover pipe from the vehicle.

Loosen the tension clamp securing the upper radiator hose to the thermostat housing with the pliers and move it up the hose until it clears the thermostat housing inlet. Twist the coolant hose slightly back and forth to break it free from the thermostat housing and remove it from the thermostat housing.

Remove the thermostat housing bolts with the socket and ratchet. Remove the thermostat housing from the engine. Remove the thermostat.

Clean the thermostat mounting bolts with the wire brush to remove any RTV sealant. Clean the thermostat housing mating surfaces with a wire brush to remove any left over gasket material. Set the new thermostat into position.

Place the thermostat housing gasket onto the mating surface and set the thermostat housing onto the engine. Apply RTV sealant to the threads of the thermostat housing bolts and secure the thermostat housing to the engine with the bolts. Tighten the thermostat housing bolts to 18 foot-pounds torque with the torque wrench.

Place the coolant inlet hose onto the thermostat housing inlet. Squeeze the tension clamp with the pliers and slide it over the thermostat housing and release to secure the inlet hose to the housing.

Place a new gasket onto the studs at the front exhaust manifold and the rear exhaust down pipe. Set the exhaust manifold crossover pipe onto the mounting studs. Tighten the crossover exhaust pipe nuts to 18 foot-pounds of torque with the torque wrench.

Place the air intake tube onto the intake manifold and onto the air cleaner box. Tighten the clamps. Connect the MAF sensor pigtail to the MAF sensor.

Remove the coolant pressure cap and fill the coolant system with the coolant that was previously removed. Start the engine and check for any leaks. Allow the engine to run until it reaches operating temperature, as the coolant cycles through the system any air in the system will work its way through the opening at the pressure cap. Shut the engine down and top off the coolant system if needed.