7.3 IDI F450 with ATS Aurora 2000 turbo and ZF5 speed with 5.13 rear gears pulling 38 foot 16000 pounds of camper, cycles, 200 gal of fresh water and 70 gal of gas (camper has generator and fuel station for gas up cycles). Never runs over 1000*F for egt and no intercooler.. The IDI is a work horse set up right...