How to Replace the Thermostat in Pickup Trucks

A number of problems can be attributed to a faulty thermostat in your vehicle. Gauges may display an incorrect engine temperature, the coolant light may come on, or the engine light may illuminate. The thermostat in your pickup truck monitors the temperature of the radiator fluid as it circulates through the engine. The thermostat is usually located in the upper end housing of the radiator hose. This end attaches directly to the water pump housing.

Instructions

1

Drain part of the radiator fluid out of the radiator. You not not need to drain all of it. Removing one gallon should clear out the upper radiator hose and water pump housing, depending on the model of truck. Position a bucket under the drain plug and use a wrench to open the drain valve. Tighten the drain plug once the gallon of fluid has been drained.

2

Use the 9/16-inch socket with the ratchet to remove the two bolts that hold the upper radiator hose mount to the water pump housing. Use a Phillips screwdriver to remove the clamp securing the radiator hose to the housing.

3

Use the putty knife to remove the housing. Once the top is off, scrape the bottom gasket off the housing with the putty knife. Remove the thermostat from the water pump housing.

4

Insert the new thermostat in the housing and apply some sealant or liquid gasket to the bottom of the upper radiator housing. The bead of sealant should be about 1/8-inch thick. Press down on the housing and slide the two bolts back into position.

5

Tighten down the bolts with the 9/16-inch socket and ratchet.

6

Reattach the upper radiator hose to the housing and use the Phillips head screwdriver to tighten down the hose clamp on the upper radiator line.

7

Add a gallon of new radiator fluid to the radiator. Check for leaks around the sealant area and on the hose clamp. Allow the sealant to dry before you start the engine.