Quite a few Nissan XD Cummins owners believe their truck is underrated with 1500-1750 lbs. of payload. Maybe, but I rather doubt it.
With all the hoopla Nissan generated about this truck having the Cummins, Aisin tranny, NV 3/4(?)-ton frame, and the gooseneck option, I can see how some would buy into all the hype (and choose to ignore the axle and payload ratings).
Hype, and ratings aside, hard to ignore the fact the Nissan Cummins uses a 6-bolt, semi-floating axle. Semi-floating axles are typically used in cars and 1/2-ton trucks. When I was in the market for one a year ago, I passed when I saw the semi-floating axle.