The load in the camper is not the issue for me. Same 5400lb camper, same WDH, same family, same load, same trips that didn't have these problems in my 1500 Sport Crew before the Rebel. Plus, most weight in the camper is eaten/drank before the trip home, which was no different either time.
I can't say it's a general Rebel problem, but can say it's a problem with my Rebel. And it seems to be more of a payload problem, as the extra weight (of the family) in the cab is what made things a whole lot worse. We weigh 540lbs as a family. Subtract 150lbs for the driver, add 650 for the tongue, I'm at ~1000 lbs payload. So, even though I'm close to the max I should be fine as I was in the other truck.
The air suspension has never complained, either. I set the WDH in Tire Jack mode, and it'll still raise it up when I take off. I even hook up in Exit/Entry, and then raise it up to Normal with no problems. And, I lowered it into Aero (which puts more work on the WDH), which didn't make a difference, either.
Regardless, I'm back at the dealer tomorrow to discuss this. I've complained to them a few times about how it handles unloaded (I get sway-ish type feelings a lot on the highway just driving to/from work, and it won't hold straight very well) and have been told something different each time: normal, get used to the electronic steering, bigger tires (which aren't bigger), etc.
We'll see... if it's "normal" again, I may be shopping for a new truck.