The CST 6"-8" Stage 1 S.T.L. Lift Kit CSK-C3-17-1 provides a superior fit, function, and finish in your 2011-2019 GM 2500HD 4WD. Improved ride quality, O.E. steering geometry, O.E. CV angles, O.E. track-width, thats just a few of the many reasons CST is known as the 2500HD specialists. You could also say they paved the way for sub-frame style lift kits, twenty years ago and long before the current trend. Fifteen years later, like the 2500HD CST Lift kits are still evolving and still continue to uphold their reputation! The 6-8" S.T.L. (Stock Torsion Location) kit uses a one piece sub-frame, fabricated steering knuckles, steering drop down and will retain the factory handling! CST has incorporated their experience in off-road racing and trophy truck quality engineering to ensure that their suspension will have increased strength, performance, overall build integrity, and perform better than stock. Throughout the initial design and R&D process CST made sure to retain the factory O.E. suspension geometry and design attributes! Â The S.T.L. (Stock Torsion Location) 6-8" adjustable kit will include a one-piece gusseted sub-frame with a steel full size differential skid plate, fabricated steel, CNC machined front steering knuckles, high strength steering drop center-link with heim jointed support links to minimize wear of the factory idler and pitman arms, differential drop brackets, heavy duty bump stop brackets, extended sway bar end links, brake line drop brackets, all of the necessary install hardware, and O.E. front shock extensions. This kit also includes the hand built S.T.L. front brackets, allowing you to keep the torsion x-member in the stock location! The rear kit includes fabricated 4" lift blocks with bump stop pads and heavy duty 3/4" zinc-plated u-bolts. Steering stabilizer brackets are built into the kit and our stabilizer shock kit can be purchased as an upgrade option. No cutting of the front differential is required or welding of any kind to install this kit. Retaining the factory front wheel track width allows this kit to work perfectly with all of the trucks stability assist features including the GM Stabilitrak system. Wheel & Tire Guidelines:Â Suggested Wheel Sizes:Â Factory OEM wheels and tires will work with the lift kit installed. Wheels For Use With Oversized Tires: Â - 17 x 8" or 9" w/ 5 1/4" BSÂ - 18 x 9" w/ 5 1/4" BSÂ - 20 x 9" or 10" w/ 5 3/4" BSÂ Some higher offset wheels may work. Test fitment requiredÂ Tire sizes for use on factory O.E. or aftermarket 20" wheelsÂ - 35 x 12.50 - 37 x 12.50 or 13.50 (trimming required - must be set to 8" of lift) Suggested Tire Sizes:Â Suspension set at 6 of lift / torsions at stock adjustment. - 35 x12.5 or similar on 8 wide wheels.Â - 315/70/17 on 8 or 9 wide wheels. - 35 x12.5 on 9 or 10 wide wheels (minor trimming required) Anything larger, taller, or wider is beyond CST recommendations and up to the installer.Â Features:Â Stage 1 Lift KitÂ Factory Like RideÂ Improved HandlingÂ Made In The USA!Â Increased Tire ClearanceÂ Near Factory Track-WidthÂ Maximum Ground ClearanceÂ Includes Extensions For OE Front ShocksÂ Notes - Please Read For Additional Components Required:Â Torsion keys required for 7"-8" of lift.Â 17" wheels must have no more than 5-1/4" backspacing. 20" or larger wheels must have no more than 5-3/4" backspacingÂ Kid includes shock relocator to re-use O.E. front shocks!Â Longer rear shocks are required and available from CST.Â Trucks with 2-piece rear driveline require carrier bearing spacer (sold separately, see below) Some models may need additional rear lift components for truck to be completely level at 8" adjustment. 2015 and newer HD models require driveshaft (sold separately, see below). 2014 and older HD models should have driveshaft or vehicle will experience driveline vibration in 4WD. (sold separately, see below). See related products below for additional add-on and upgrades.Â 3500HD Owners: This kit was designed and tested for the 2500HD trucks. It can be used on 3500HD and 3500HD Dually if the purchaser / installer is able to provide custom u-bolts for their application. Due to the many different spring and axle configurations, u-bolts are not included or offered for the 3500HD models. Neither XDP or CST offer u-bolts for these applications. You must be able to source them locally. Custom carrier bearing spacer may be required as well. Â Truck Freight Item: Allow 1-2 Weeks for delivery. Truck freight charges apply.