Readylift 7-8" Front with 5.0" Rear lift kit part # 44-3051 (with 4 SST3000 shocks) fits 2011-2015 Chevy/GMC 2500HD-3500HD 4WD.  It allows for up to 37" tall tires, which may also be purchased thru Marken Performance.  This kit features precision laser cut and CNC formed bolt-in sub-frame assemblies along with custom formed nodular iron knuckles engineered to provide perfect geometry, ride and handling performance. It also includes an integrated differential drop bracket system to insure correct CV axle angles on 4WD applications and maximum performance in 4WD mode.  The front lift is provided by ReadyLIFT Forged Torsion keys that will provide adjustable lift from 7 inches to 8 inches while maintaining the factory ride.  To lift the rear, this system includes OEM quality cast iron 5.0" tall rear block that doesn't sacrifice the ride.  Also includes tough steel bump stop extensions, skid plate and sway bar end links.  The sub frame and other components are powder coated with a unique and improved Plascoat finish.