Supreme Suspension heavy duty steel lift shackles have been designed to lift your trucks rear-end 2" over stock. CNC machined from high-strength steel and coated to protect from corrosion in even the roughest conditions. Our differential shim kit has been specially engineered to help correct the pinion angle of your vehicle back to factory specifications. An incorrect pinion angle can cause driveline vibrations when driving at speeds, and will severely shorten the lifespan of the differential pinion bearing. CNC machined from billet aircraft aluminum, these are designed to never compress or change angle. They're also manufactured with provisions for center axle alignment pins, and utilize raised grip steps to help keep all components secured in place.NOTES: An alignment is always recommended after altering the height of your vehicle.