For an affordable solution to run 33" tires on your GMC Sierra, try this 5" Combo kit by Performance Accessories. This kit consists of a 3" body lift and 2" leveling kit. Installation will not affect electronic stability controls.
This PLS system comes with high-grade components including nylon-reinforced body blocks, aluminum upper coil spring spacers, precision laser cut and powder coated steel bumper brackets, and urethane Gap Guards. Can be used with OE wheels.