Our Free-Spin Kits are made in USA for us by Dynatrac for your popular Ford Super Duty 4x4 and are engineered for a lifetime of trouble-free operation. Torque King® Dynatrac Free-Spin Kits include heat-treated chromoly dead spindles, Timken® wheel bearings and seals, 35-spline 1.50-inch chromoly outer shafts, wheel hubs, Warn locking hubs, and all necessary tone rings, studs and hardware. Torque King® Dynatrac Free-Spin Kits replace problematic unit live spindle front hub assemblies that have closely spaced, non-adjustable, and non-serviceable wheel bearings with widely spaced, replaceable, and adjustable wheel bearings. By spacing the bearings farther apart, the wheel and tire assembly has less leverage on the bearings, reducing wear and increasing bearing life. Torque King® Dynatrac Free-Spin Kits have a dead spindle design which means the spindle is solidly bolted to the steering knuckle and it does not rotate with the axle shaft like Dodge Ram or around the axle shaft like a Ford. Having both locking hubs and dead spindle design means your front axle wear will be decreased and chances are your 4x4 will get measurably better fuel mileage.