How do you change the thermostat on 2004 Cadillac Escalade?

To change the thermostat on a 2004 Cadillac Escalade, first, ensure the engine is cool and disconnect the negative battery cable. Drain the coolant from the radiator and remove the upper radiator hose connected to the thermostat housing. Unbolt the thermostat housing, replace the old thermostat with a new one (making sure to align it correctly), and reassemble the housing and hoses. Finally, refill the coolant, reconnect the battery, and check for leaks.