How do you replace thermostat on Chrysler 300?

To replace the thermostat on a Chrysler 300, first ensure the engine is cool and disconnect the negative battery cable. Drain the coolant from the radiator, then remove the upper radiator hose and the thermostat housing. Take out the old thermostat, clean the mating surfaces, install the new thermostat with the correct orientation, reassemble the housing and hose, refill the coolant, and reconnect the battery. Finally, run the engine to check for leaks and ensure proper operation.