I drained all coolant from radiator (using red plastic drain), and engine block (using hose going into the oil cooler behind oil pan)
I assume the only coolant left in the system was heater core.
Upon refilling, it only took 1 1/2 gallons of coolant mix. Is this right? I thought I read the cooling system was 3 gallons. No way 1 1/2 gallons was left in heater core. The car reached normal temp no problem, and ran fine.