FDCF1

I have a 2003 F150 Heritage 2 wheel drive with the 5.4 Triton and automatic transmission. I am trying to replace a leaking Pinion Seal. I went and purchased the set, seal, nut, and yoke, and when I started taking it apart it became obvious that they were not the same size. The original is quite a bit bigger but no one at the parts store can find a listing for it. Does anyone know where I can find the correct parts or at least listings to know what to order?

PerryB

Hopefully you haven't backed off the pinion nut yet. You don't want to replace anything but the seal. Changing the nut and yoke prevents you from returning the pinion nut to its previous preload. That's very important. You can't just torque it to a certain value, and you can't just rattle it down tight with an impact gun. The correct proceedure is to count the protruding threads (through the nut) and then index mark the pinion shaft and nut. After replacing the seal, return the nut to it's original position and then add a couple degrees more rotation in the tightening direction. This increases the bearing preload slightly (not critical) AND puts positive compression on the crush sleeve, which keeps the pinion nut tight (critical). If you can't correctly restore the crush pressure, you have to pull the axles and ring gear, replace the crush sleeve, and then re-establish the pinion bearing preload.