2" Front 3" Rear Leveling Lift Kit For Chevrolet Sliverado GMC Sierra 1500 WHAT IS A LEVELING KIT? If you own a truck, you’ve probably noticed that the rear of the truck sits higher than the front. As a truck is built to haul heavy loads in the bed, the additional height in the rear is intentional so the truck doesn’t sag when extra weight is added. However, when you’re not hauling something, it might not be the most visually appealing. One easy way that you can fix this is with a leveling kit. A leveling kit allows you to raise the front of the truck a few inches to match with the back. .