I just bought a 2000 Dakota Sport (4.7 V8) w/ 100K miles. This truck is awesome and I'm totally happy with it... but I've noticed that the temp gauge fluctuates from the "normal" 210/220F to up close to 240/250F when I'm on the highway driving 70mph and up with RPM's around 2500. As soon as I let off the gas and go back to slower speeds the temp goes back down. The gauge never goes above 260F or in the RED but it gets close. Occasionally, I hear a gurgling sound coming from the radiator cap area when I shut off the engine, but not all the time. I have noticed a small amount of anti-freeze overflow on and around the engine, but not much, and the fluid level is still good. I'm concerned that when the weather turns hot my truck may overheat and I want to fix any potential problems before I end up hurting my engine. Should I be worried? Is this normal? Please help.