I am running 38's currently and using 4:56 gears. That actually gives me a slightly "taller" gear than the 3:73 and 29's. It is nice the truck doesnt seem to be wound up so tight. I think you would be very pleased with 4:56 gears. I was also told not to run anything over 4:56 with the kind of torque our trucks make since the pinion gear starts to get really small.