Our lightweight extruded aluminum lowering blocks are stronger than billet! Available in several heights, all 2-1/2" wide, 5" long. The centering pin is 9/16". These blocks will increase or decrease suspension height on most leaf spring applications and can be installed below the leaf spring to raise the vehicle or on top of the leaf spring to lower the vehicle. These lowering blocks allow you to lower your leaf spring vehicle by up to 4 inches. Lightweight aluminum lowering blocks are stronger than billet