we own a 1999 dodge durango V8 5.2 liter engine...have been having issues with it overheating....at first it seemed to be the water pump, replaced that and ran fine for a while. then the thermostat went replaced that and ran fine, now it started overheating again...everything lead towards it being the thermostat again so replaced it again. ran fine for a few days and is getting too hot again...it never actually "overheats" but gets pretty close. we checked fluids while car was hot and cold and it is always full...cant fit anymore antifreeze in it. also, it doesnt get hot if i just take it to the store and back it only gets near overheating after driving continuously for about 15 minutes. any suggestions would be greatly appreciated!!