Over 8,500 gvw F-250's have eight lug hubs and a full floating rear axle.
As a running change during the 1985 M.Y. Ford started using the Sterling 10.25 rear.
With the Dana prior to that you have to pull the axles to get the brake drums off.
The light 250 (7,700 lbs) they had a "semi floating" rear, where the hub was flush with the drum, and didn't have eight lugs.
Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.