How do you change the thermostat on a 2001 Pontiac Montana Minivan?

To change the thermostat on a 2001 Pontiac Montana Minivan, first, ensure the engine is cool and disconnect the battery. Then, locate the thermostat housing, which is typically near the engine's upper radiator hose. Remove the hose and the housing bolts, take out the old thermostat, and replace it with a new one, ensuring the gasket is properly seated. Reassemble everything, reconnect the battery, and refill the coolant as necessary.