2000-2010 Sierra 2500HD Lift Kit 1.5 Rear Solid American Cast Iron Lift Block FITMENT: 2000 - 2010 GMC Sierra 2500HD 4WD/2WD CONTENTS: 2 solid American made cast iron rear suspension tapered lift blocks SPECIFICATIONS: 5.7 Inch Length, 2.5 Inch Width, 1.5 Inch Height TECHNICAL NOTES: Install the tallest ends of the tapered blocks to the rear of the vehicle BENEFITS: American Automotive solid cast iron lift blocks are stronger than aluminum and cast as a single, more stable construction than blocks with pressed pins; They are designed to increase rear load capacity and provide for an ideal tow package upgrade; American blocks absorb noise and vibrations, and are tapered for perfect pinion alignment