Not sure, but you have two options; lower the back, or raise the front. I recommend you raise the front approx. 2" so you will "level out" the truck. If you don't plan on having large tires, you can lower the back. But I don't exactly know how to do that. Remember, the rear is raised so that when you haul things in the flatbed, the weight will then even out the truck. Lower the rear, and your truck will sag-in-the-back when hauling ATV/Bikes/Ect.