Quote Originally Posted by JohnK View Post
One of my other hobbies (OK, obsessions) is espresso. Pretty much all espresso machine manufacturers recommend against using distilled water in espresso machines as it is corrosive enough that it will damage boilers over time. The whole topic of "proper" water for espresso machines is one giant rabbit hole, but it makes sense that you wouldn't want to use distilled water in your cooling system for the same reason. Count me in the KISS camp - I just used the pre-mixed Motorcraft 50/50 that Ford recommends for the coyote.

And there you go,KISS