I have a 2017 Ram 3500 DRW with the factory air bags, Laramie package with 4:10 gears.
If I were to do it over I would go with the std leaf spring suspension. The air bags cause more sway. Adding a sway bar helped. If you go with the std leaf springs you can always add the airbags later if you feel the need but with the beefier spring pack they would be needed less and carry a smaller percent of the load. Our 2004 Ram dually had less sway with the same camper despite a lower GVWR.
We used to own an Arctic Fox 1150 and did a trip from central CA to Alaska for a few months. Other than the factory airbags we love our Ram. I'm sure others are just as happy with their Ford. Unfortunately the slide on our AF1150 broke again on that trip and we decided to try a different brand for our current camper.
Dual alternators isn't something I optioned. What would you be adding that would require dual? No uplifts either. I think the call on alternators depends on what you plan on using the trucks charging system for. If it's just to maintain the truck battery and provide power through the 7 pin plug a single alternator should be fine.
If all you are hauling is the camper 3:73 would be fine. If you are going to be towing decent weight as you describe the 4:10 will give you a little better towing power, but 3:73 would still work.
I would test drive both trucks. We are on our 3rd Ram Cummins TD and have been very happy with all three, especially our new truck with the exhaust brake and gobs of power from the Diesel engine. It really flattens out the mountains even at 21k gross or so.
2022 Ram 3500 Laramie CTD DRW Crew 4x4 Aisin 4:10 Air ride.
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