The first place I would look is my Ford dealer.
The second place I would look is a Ford dealer that is a sponsor of TheDieselStop. Wabash Ford in Indianapolis. Their website is
Your Premiere Source for Ford Truck Parts and Accessories
If that doesn't get you there, then start on their index at
Universals and rear axle
then Rear Axle
then Propeller shaft
then Slip Yoke. About $75. But call them to sure that one is for a diesel.
