F 350 4WD Super Duty V10-6.8L VIN Z Bi-Fuel (2001)
5. Install the differential pinion shaft and the differential pinion gears.
6. Position the right differential case half with the index marks aligned.
7. Position the differential case retaining bolts.
8. NOTE: Use the special tool as shown to keep the differential case from turning.
Tighten the retaining bolts.