ReadyLIFT is excited to offer a new heavy-duty suspension lift option for the 2020-2021 Chevy Silverado and GMC Sierra 2500/3500 HD trucks?including the popular AT4 package. Along with the outward appearance changes to the new GM HD, General Motors also made changes to the long-standing torsion bar suspension. These changes required ReadyLIFT to engineer a new? SST lift kit that is specifically designed to function and install properly on this new suspension design. Our dedication to professional engineering and manufacturing has yielded a new 3'' SST lift kit system that comfortably allows for 35'' tires.For those who want a lifted stance all the way around on their new 2020-2021 GM HD truck, we offer the 69-3030 3''/2'' SST Lift Kit. This system provides 3'' of adjustable front lift with new forged torsion keys specialized for this 3'' front lift (not the same keys found in 66-3020). Taller differential drop spacers and skid plate spacers are included, as well as new taller bump stops, rear shock extensions and our popular OE style cast iron 2'' tall rear lift blocks with new longer U-bolts. The 69-3030 SST lift kit works with trucks equipped with either the OE #84461807 or OE #84634344 factory torsion keys and requires ReadyLIFT torsion key unloading tool 66-7816A or similar for installation.Can be used on trucks equipped with factory snow prep/plow packages.