Just wondering what the factory one is, and if it's safe to use a different temp. Since the factory gauges aren't numbered, I don't know what temp it's running at, but it always gets to the halfway point on the gauge, no higher. Wondering if that's normal, and what the optimum temp is for the 4.7, because since I bought it recently I want to make sure it's running like it should, being the wife's ride I want it the most reliable vehicle we have.