I do not want to overstate this point, but in my opinion the majority of truck camper owners exceed their truck ratings for exactly what you discovered too late. I am within my truck ratings, but my dry weight camper leaves to camp more than 1,000 pounds heavier. You have Timbrens and if you need can still add a sway bar or if you have one a heavier sway bar and more serious shocks such as Rancho 9000s or Bilsteins. Many of us have thrown everything but the kitchen sink to make these pigs handle and you can do the same and probably would no matter what truck you had chosen.
So stay loose and Andra is my wife, I am Steve. 🙂
Steve and Andra
2012 F350 6.2 gasser SRW LB
Fab Fours front and rear in case we run into a rhino
2019 Northstar Laredo SC