Most pickup trucks are made with a rake & the rear is normally a little higher than the front, so that they sit level when fully loaded. These leveling kits improve the look of the truck by raising up the front to match the rear (when unloaded). Each kit is a little different for each vehicle application & they work with the stock springs and shocks. Includes all hardware and detailed instruction sheet. Fits: 1999-2006 Chevy Silverado 1500 4WD 2007 Chevy Silverado 1500 Classic 4WD 2000-2006 Chevy Tahoe 1500 4WD 2000-2006 Chevy Suburban 1500 4WD 2002-2006 Chevy Avaanche 1500 4WD 1999-2006 GMC Sierra 1500 4WD 2007 GMC Sierra 1500 Classic 4WD 2000-2006 GMC Yukon 1500 4WD 2000-2006 GMC Yukon 1500 4WD 2000-2006 GMC Yukon XL 1500 4WD