13. Have your heater temp. control in the max heat position
14. Slowly add new coolant (50/50 mix of water and antifreeze) to the expansion tank until the level is at the Cold Fill Range mark (CFR).
15. Leave the expansion cap off and turn the engine on until the thermostat opens and the upper hose is going to get hot. Make sure you perform this test in a well vented area.
16. Turn the engine off and let it cool. Add more coolant to the CFR mark in the expansion tank again.
17. Squeeze the upper radiator hose to expel the air and then add more coolant mixture if necessary. I recommend replacing the expansion cap at every 100k miles.
18. Start engine and allow it to reach at a normal temp and check for leaks.
19. This is very important. Set the heater and blower controls to the max settings and check if the heater output from the air ducts is warm because that would be a good indication that all the air has been purged from the cooling system.
http://mustangforums.com/forum/2005-...ml#post6298822
Nope just follow these procedures and you should be good.
Coolant Flush
