Anybody done a drain & flush of the cooling system? Does the 4.6 block have block drain plugs? A local shop I trust charges $109 (includes coolant). I wonder if it's worth doing myself or have them do it. They install Zerex G-50 (gold) which meets the Ford spec. Thoughts?
are they hooking up a machine and flushing the system with pressure, or just draining and refilling? many shops will make a shortcut, but you said they are trustworthy. If you dont have a way to flush the system out at home, i say take it in. i am not sure if we have block drain plugs or not, but knowing ford, i would say no.
Since the car's only a couple of years old (mine's 4 years) I just drained the radiator and disconnected the lower hose from the engine. It's not like you'll be draining an old corroded system. If you change out the coolant every 2-3 years that's all that's needed along with a bottle or 2 of water wetter. I live in Maryland, my garage still gets cold at night so I went with a 60-40 mix (mostly watter) and 2 bottles of watter wetter. With that mix my maximum temps in the summer are about 8-10 degrees lower than before.