Works with both 4X4 and AWD. INNOVATIVE PATENTED design Leveling / Lowering kit allows total control of ride height 88-98 Early 1st design 1999-07 Classic All 4x4 models GM HD 2wd and 4wd with torsion bars. Super 'T' MAXX Tool ( SMX-MT ) required for easy installation. Retains OE length shocks & ride quality Lifetime Structural Warranty