If you use your truck for towing and hauling heavy loads, the Nitro kit will deliver a factory ride quality, and allow for extra clearance for larger tires and wheels. Plus it gives it an aggressive stance thanks to the additional rake. 2.5 inch Nitro Kit: 2.5 inch Front Precision cast constructed with a durable powdercoat finish Torsion Key with Shock Extension/1.5 inch Rear Blocks with U-Bolts. Recommended 33 inch Tire Size.