I'm already driving through 16-30f every night this week, and driving my truck runs at 191-200f the whole time,I idle for about 3 hrs in green river, and it was 17f when I woke up and my water temp was 188, the electric fan is an awesome design, and on the highway, so far the temps are normal, but I might buy some grille "inserts" I saw on eBay that are chrome,I might just install them on the two lower slots because the grille shutters only cover the top two.