How Do I Replace the Thermostat on a GMC K2500 Sierra Pickup?

The thermostat is a component responsible for regulating the engine temperature. Without a properly functioning thermostat, the engine will overheat, and the heater will blow out cold air. Thankfully, changing the thermostat is a simple process that will take you less than a half hour to complete; doing the job yourself will save you the costs of taking your truck to a mechanic. Just a couple of wrenches and a new thermostat will have your truck blowing hot air soon.

Instructions

    1

    Drain the coolant into a container until the coolant level dips below the thermostat level.

    2

    Follow the upper radiator hose to the engine to locate the thermostat housing.

    3

    Loosen the clamp on the radiator hose, using the fat-head screwdriver, and pull the hose off the thermostat housing.

    4

    Remove the bolts that hold the thermostat housing to the engine, using the proper size wrench.

    5

    Clean the old gasket material from the thermostat housing and the engine.

    6

    Insert the new thermostat into the engine, with the spring going into the engine.

    7

    Place the new gasket and the thermostat housing onto the engine and tighten the bolts, using the proper size wrench.

    8

    Replace the radiator hose and tighten the clamp, using the flat-head screwdriver. Do not over-tighten.

    9

    Replace the coolant that was drained from the engine.

    10

    Start the engine and check for any leaks around the work area.