I don't know anything about the interchangeability of the 8 lug drums with the 10 lug disc. I have a feeling that they could be interchanged, if you would like me to measure mine I can.
The complicated part of changing to disc in the rear in then having to do it in the front, are you up for that?
Or, is it possible that there is a 10 lug drum Dana 70HD or even an 80, I believe that the outer ends of the 70HD and an 80 are identical.
As for the GVW, If the truck weighs about 5,000 and it can weigh 16,000 loaded it seems to me that a 10,000 rear might be enough?
