Let truck warm up for 5 minutes then drove around town unloaded for about 20 minutes with ppe standard hooked up and engine temp did not go higher than 165f. Got on the free way and romped on it till I reached 75mph and cruised at 2200 rpm for about 3 miles and temp did not get higher than 170f. Cruised back home into town and truck was sitting at 168f before it shut her off. It's 55 degrees Fahrenheit here today. I've owned the truck for about 6 months and it's never reached the 180-195 operating range. Will new t-stats fix this?