When creating diluted coolant by adding water to a concentrate, yes, distilled water is the way to go. I am referring to the post above by
@Majestic which I interpreted to suggest using ONLY distilled water in the cooling system. In that case, no, as this creates a condition similar to using only de-ionized water, where the chemical structure of the water will begin to corrode the inside of the cooling system. Bottom line, I would never want to use any sort of straight water, be it tap, distilled, or deionized, in a cooling system that sees any sort of long term use.
All that being said, I admittedly may have misinterpreted that post where he actually meant using it to dilute a coolant concentrate.
But in my case, the Motorcraft Orange comes prediluted, so no need to add any sort of water. I was more curious about adding water wetter to that mixture.