F53 coolant change with motoraide

Just finish helping a friend yesterday. Dump the engine first then removed the line going to the back. We used a pump and flush out the rear until clear. did the engine the same way. Then used low pressure air 10 lbs and push out the clean water from the back. Engine the same way. As stated use the color that came out. Premix and pump it back into the back till it runs out. Connects the hoses back to engine. Fill up engine and run to get rid of the air. We had over five gallons in the bucket. Did not measure it. Just filled it back and ran and drove it till no more air. He purchase 4 gallons and then mix 50/50. He has a few more day to run around and top off as needed. All hoses were replace also along with thermostat.