How many of us are there? Owners of Dodge based RV's?

If the side against the wheel, is flat or concave, the nuts should be securing Hub Piloted Wheels. If the darker gray in the pic is the Hub, then that tight mating line between white and gray suggests Hub Piloted. Make sure the hub and wheel surfaces are clean and rust free, and nut/stud threads clean. Then torque to spec on a criss-cross pattern. For the 1991-current year Ford E-3/450 with 9/19" studs, torque spec is 140-ft-lb. Stamped right into every nut.