I have a very similar truck 2001 F250 4x4 CC SRW long bed auto with 315/75/16 and have done the stage 1.5 injectors, TS Chip, S&B cold air intake, and 4" turbo back exhaust and am still running the 3.73 gears and stock transmission. I tow mostly local with my gooseneck and farm tractor and...