The body lift option is only for if you have a body lift installed on your vehicle. If you have any type of suspension lift (coilovers, new shocks and coils, spacer lifts, leveling kits, etc) you will want to select the "no body lift" option. This is because while a suspension lift raises the entire vehicle together, a body lift only spaces the body off of the frame. Since our bumpers are mounted to the vehicle’s frame, a body lift will result in the bumper being left behind while the truck body moves upwards by the height of the body lift. This will result in an unsightly gap between the bumper and body. The 1" body lift version of the bumper is designed to be 1" taller to correct for this gap created by the body lift. To achieve this, we actually re-dimension the entire bumper to ensure a perfect fit and great proportions! It is highly recommended to plan your bumper and body lift together at the same time.