Wheels make a small difference, but the main problem is that all the manufacturers have taken to "rake" to make their trucks look more manly. The body is designed on the frame to run slightly nose down. Pure esthetics. Since they can't lower the front bumper without sacrificing ground clearance, they raise the rear.
Put a long carpenter's level on the bed rail and you can see it.
I'm not sure about Rams, but on GM products there is an easily installed link that lowers the rear of the bed 1.5 or 2 inches. Realize that you loose about half of that in wheel travel to the stops, but if you have the standard size wheels it should not be a problem.
A lot simpler (and cheaper) than raising the trailer suspension and unless it s parked right next to an unmodified example it is invisible.
A