Thought i'd let ya'll know something I learned the hard way. Fought an overheat problem for almost a year, always under load, or just gougin on it. My temp gauge would climb like a tach, wouldn't blow smoke, I couldn't figure out if I was rich or lean or what the hell. Well, to make a long story almost bearable, DON'T use an aftermarket water pump on your cummins!!!!!!!! At 110,000 miles I had installed an O'rielly pump. Looks the same usually, I found 1/16 inch difference in depth. Put on the 280.00 cummins pump, cured the problem instantly. I usually pull 10-15000 lbs, tractor,etc. By the way, I thank ya'll for the site and feedback,don't get on here much,in the woods here in east Texas,all we can get is dial-up, it gets frustrating. (05 2wd 2500,no programmer,just kn filter) hdmech