It's summer in Georgia, and I was pulling a trailer last week, and noticed that my temperature gauge was creeping up above normal (typically, needle is exactly at halfway point), especially when I was sitting at a long red light, or in slow or stopped traffic. I figured it was either the thermostat or fan clutch. I ordered both thermostat (with new gasket) and fan clutch, and installed both. First checked out some tutorials on this site, as I'd never done these before. Pretty straightforward and easy. Worst part was removing and replacing the 4 fan bolts - there's no room in there to work at all. Everything is good now. I can now sit at idle for long periods of time, and the temp gauge never goes above normal.