Supreme Suspensions - 1999-2018 GMC Sierra 1500 Lowering Kit 2" Rear Steel Drop Shackles Suspension Drop 4x2 4x4 PRO FITMENT: 1999 - 2018 GMC Sierra 1500 (2WD 4WD), Fits 6-lug models only. CONTENTS: 2x Rear Carbon Steel Shackles, Installation Instructions and Pro Pack. INSTALLATION: Easy 'bolt-on' installation takes 1 - 2 hours. No special tools are required. TECHNICAL NOTES: Designed to drop your ride 1 to 2 inches. Maintains factory ride quality. BENEFITS: Improves your handling by lowering your center of gravity and gives your ride that cool lowered look. (2x) Rear Carbon Steel Drop Shackles Installation Instructions Supreme Suspensions Pro Pack