Greetings all. About 5 months ago the old girl started loosing water. Discovered the weep hole was draining so I had a new water pump put in it. Don?t know if they did a thermostat at that time. All has been fine until this week. I live in Florida and the temp has always been rock solid at 210. No mater how hot or whatever I am towing. Anyway this week I noticed the gauge climbing. That night I added some water and figured all would be good. Drove to work in the morning and all was good but it was cool out. On the ride home it was 93 and began heating up. It never got to the 235 mark but close. By the time I got home it had split the seam on the overflow tank, but never puked out the overflow hose. I stopped and bought a radiator cap hoping that was it. Next morning fine again. Yesterday evening was a nightmare again. Doesn?t do to bad as long as you are moving but stop and go get warm quick. Fan seems to be working correctly. I can let it run in the driveway for an hour with the ac running and it?s fine. When you drive it in the heat of the day is when it has issues. So the truck is 2003 1500 4x4. 185k, rebuilt trans and transfer case a year ago. Original motor with no major work ever performed. Never wrecked. Never seen the temp gauge change no matter what. Where should I start?