F 250 2WD Super Duty V8-6.0L DSL Turbo VIN P (2004)
5. CAUTION: Whenever the cups are replaced, the differential pinion bearings must also be replaced.
Make sure the cups are properly seated in their bores.
If a feeler gauge of the specification shown in the illustration can be inserted between a cup and the bottom of its bore at any point around the cup,
the cup is not properly seated.