F250 Super Duty. F350 Super Duty. F450 Super Duty. F550 Super Duty. 4,600 Lbs. Front Axle. Bearing Only. Dana Axle. Differential Carrier Bearing. Drive Ratio 4.88. Heavy Duty Towing Package. Ring Gear 9.75". Single Rear Wheels. Wheel Bearing. Assembly - Ball. Carrier. Case. Inner. Side S. Wheel.