I would not tow without an intercooler. It helps with EGTs a lot. My toy hauler is 8500lbs dry. Loaded it's over 11000lbs eze. I tow from Cali to Oregon etc with BIG hills. My EGTs don't ever get over 1000 and pull the big grades 45-55. I also have a Banks turbo, Swamps single shot injectors, HPOP, DP custom tunes, fuel cross over, 3pod gauges, boost fooler, Diamond 3inch down pipe to a 5inch ext no muff, John Woods trans with billet internals, trans cooler with inline filter, etc.