Front Leveling Kit | 2.5" Lift | Upper & Lower - for 2007-2014 Chevy Avalanche Silverado Suburban Tahoe GMC Sierra 1500 Yukon 2WD 4WD 4x2 4x4 [CHEVY & GMC APPLICATIONS] 07-13 Avalanche. 07-14 Silverado 1500. 07-14 Suburban 1500. 07-14 Tahoe. 07-14 Sierra 1500. 07-14 Yukon. 07-14 Yukon XL 1500. [LIFT INFORMATION] Install Location: Front Upper & Front Lower. Total Lift Height: 2.5" (2.5 inch). [UPPER SPACERS] Made from Aluminum. Thickness = 1 1/8" (28mm). [Lower SPACERS] Made from Steel. Thickness = 5/16" (7.5mm). [IMPORTANT] Your suspension geometry is not 1:1 ratio. Meaning the Actual Item Thickness is NOT equal to the lift height. See Thickness Information above. In addition, an alignment after installation is necessary to get the correct lift.