2015 Dodge 3/4 Ton Really Not Camper Compatible?

Diesel engine in all brands takes out a bunch of payload.

6.7 Cummins engine: 1190 lbs.
6.7 Powerstroke: 970 lbs.
6.6 L Duramax LB7: 836 lbs.

If you want max payload, you have to go Diesel DRW, or if you desire a SRW, get a gas SRW.

Hemi 5.7 L : 590 lbs.

Not really all the surprising that a 2500 class truck has little payload. Surprising the dealer actually had some ethics and didn't want to put the customer and his family in jeopardy to make a buck.