The ReadyLIFT 7" to 8" Adjustable Lift Kit Systems are specifically designed for 2011-2019 Chevy Silverado / GMC Sierra 2500HD/3500HD 2WD/4WD trucks. This kit includes four Bilstein 5100 Series Performance Shocks tailored for this system. This kit is designed to provide a quality lift and off-road durability while preserving the factory ride on the street. The kit, known as 44-3072, comprises precision-engineered laser-cut and CNC-formed sub-frame assemblies that bolt directly in place. It incorporates custom-formed nodular iron knuckles for ideal geometry and handling performance. Additionally, there's an integrated differential drop bracket system to maintain correct CV axle angles on 4WD setups and enhance 4WD performance. For the front lift, the ReadyLIFT Forged Torsion keys are utilized, allowing for adjustable lift from 7" to 8" while keeping the factory ride quality. In the rear, an OEM-quality cast iron 5.0" tall rear block is included to maintain ride comfort. The kit also features steel bump stop extensions, a skid plate, and sway bar end links. Please note that this kit is compatible with stock 20" wheels or 9" wheels with 4.75" - 5.5" backspacing. However, it cannot be used with stock 17" or 18" wheels. The sub-frame and other components are coated with Plascoat finish, a durable polymer alloy coating designed to withstand stress cracking, abrasion, impact, and factors like weather conditions, detergents, salt spray, and pollutants. Please be aware that Single Rear Wheel (SRW) models may require custom U-Bolts to accommodate the factory tow package, and the installation of this kit may reduce towing capacity. This kit is primarily intended for 2WD use at speed on public roads, and 4WD should only be used off-road or in adverse slow-speed conditions due to potential driveline vibrations at high speeds. In some cases, a double cardan driveshaft may be necessary to mitigate high-speed 4WD front driveline vibrations for kits ranging from 5" to 8" in height.