An Eagle Cap Camper Snapped A Ram 3500 Dually In Half, Mopar Refuses $17,000 Repair Bill

Reading the acritical it states that "the actual payload capacity of the truck in question is itself in question. While the max payload capacity for a 2020 RAM 3500 is 7,680 pounds (3,483 kg), that’s specific to the regular bed, long-bed model with two-wheel drive and a 6.4-liter V8 engine. The truck here is a crew cab 4×4 dually with a diesel engine which means that its payload capacity is probably closer to 5,850 pounds (2,653 kg)."
I would have thought the payload capacity of the dually would be higher than a regular 2wd version.