The front axle on a Ford F-350 has a set of hubs on the front axle shafts. These hubs help hold the axle oil inside the axle tubing through the axle seals. Should the axle seals wear down, then your axle could leak oil, and this may cause the axle to fail. To prevent or resolve this problem, you need to install a new set of hub seals on the axle.
Park the F-350 and set the parking brake. Lift the front axle off the ground with the jack and put jack stands under the axle. Take off the front wheels using the tire iron. Set the wheels to the side.
Loosen the hublock screws -- located in the center of the rotor -- with the 3/8-inch ratchet and socket. Insert the tip of the pry bar between the hub flange and the hub, then pry the gasket out of the hub flange. Remove the hublock screws with the 3/8-inch ratchet and socket. Use the pry bar to remove the hublock from the hub. Pull off the O-ring from the hub with your hands.
Install the new O-ring on the hublock with your hands. Turn the hublock dial to the "lock" setting. Use bearing grease to grease the inner and outer splines on the hub.
Rotate the wheel hub with one hand while putting the hublock into the center of the hub with your other hand. Firmly push the hublock to lock it into the hub. Turn the hublock dial to the "auto" position.
Install the hublock screws using the 3/8-inch ratchet and socket. Reinstall the front wheels using the tire iron. Lower the F-350 off the jack stands with the jack.
