I just traded my CJ5 for an 89 D250 with the cummins. It's bone stock and needs some love as far as suspension goes. Anyway, I've toyed with the idea of using it for the truck camper but all the stick...
I would replace the tires before I hauled anything of size with it. In fact I'm still going through the barely livable brakes (on an empty truck). I know my rear is a dana 70 and has 3.07 gears. Beyond that I can't seem to find any reliable info. The 5500 has come up a few times but I've seen so many different numbers tossed out I'm not sure who to trust.