Genuine Ford F-150 Differential Seal

Ford F-150 Differential Seal Parts Questions & Answers

• Seal Assembly - Oil
  BR3Z-4676-A
  Q: How to replace a pinion seal on a Ford F-150?

  A: Loosen the wheel lug nuts. Raise the front or rear of the vehicle and support it securely-on jackstands. Block the opposite set of wheels to keep the vehicle from rolling off the stands. Remove the wheels. Disconnect the driveshaft from the differential pinion flange and support it out of the way with a piece of wire or rope. Rotate the pinion a few times by hand. Use a beam-type or dial type inch-pound torque wrench to check the torque required to rotate the pinion. Record it for use later. Mark the relationship of the pinion flange to the shaft then count and write down the number of exposed threads on the shaft. A special tool or a chain wrench can be used to keep the companion flange from moving while the self-locking pinion nut is loosened. A screwdriver or long punch inserted through one of the holes in the flange can also be used to immobilize the flange. Remove The pinion nut. Withdraw the flange. It may be necessary to use a two-jaw puller engaged behind the flange to draw it off. Do not attempt to pry or hammer behind the flange or hammer on the end of the pinion shaft. Pry out the old seal and discard it. Lubricate the lips of the new seal and fill the space between the seal lips with wheel bearing grease, then tap it evenly into position with a seal installation tool or a large socket. Make sure it enters the housing squarely and is tapped into its full depth. Install the pinion flange, lining up the marks made earlier. If necessary, tighten the pinion nut to draw the flange into place. Do not try to hammer the flange into position. Apply a bead of RTV sealant to the ends of the splines visible in the center of the flange so oil will be sealed in. Install the washer and a new pinion nut. Tighten the nut until the number of threads recorded earlier are exposed. Measure the torque required to rotate the pinion and tighten the nut in small increments until it matches the figure recorded earlier. To compensate for the drag of the new oil seal, the nut should be tightened a little more until the rotational torque of the pinion exceeds the earlier recording by 5 in-lbs. Reinstall all components removed previously by reversing the removal process, tightening all fasteners to their specified torque values.