Rick your onto it. The STANDARD 9" Ford rear (removable center section) did not come with "sealed bearings", and replacing the axle seal on these is as I stated above. This style bearing MUST get "oiled" from the rear end
oil in the tube of the housing.
Sounds to me like Shell Valley and some others have modified the Ford axles/housing to accept sealed bearings or a non standard type of seal for the the bearing area. OR, Ford offered a "light wieght" style 9" that used "sealed bearings"? I am not aware of a "stock" Ford 9" that used "sealed bearings".
Ernie