Cognito 24-24 Chevy/GMC Silverado/Sierra 2500 Super Stock KitThe 2500HD AT4X and ZR2 already comes 'leveled' from the factory via torsion bar and torsion key clocking. These models are coming the same size in the front as our 3" leveling kit on the other models. Of course you have already noticed that the truck is not level, and that is due to GM adding a 1. 5" tall lift block to the rear. The OEM upper control arms, knuckles, and lower control arms are all new and specifically designed for this model. THe OEM