I agree with dana44 and valiant 67. I've flushed the cooling system three times in the nine years that I've had my 3.8 T&C. Never did anything but fill with coolant, idle the engine (with a few blips) until the fan goes on, and then top up the radiator and add coolant to the overflow bottle to the indicated level. Never had a problem with air in the system. I would advise replacing the steel coolant return pipe if it's rusty. It runs under the crank pulley and connects the lower radiator hose to the water pump housing. It's an easy R&R.