Well, you have what you got, so how do you want to outfit it? My '06 F350 rides like a dream with upper and lower Stableloads, but I'm only carrying 3200 lbs. fully tanked. A newer truck should have more wiggle room I think. My GVW is 11,500 and I'm about 500 under, more or less. What is more important to me is what the "seat of the pants meter" tells me in terms of drivability and stopping power. I don't wobble to and fro when pulling across pavement transitions and the wind doesn't usually bother me either. It squats only about an inch or so and it looks well balanced. How does yours compare to mine... and be brutally honest. If my hunch is correct you could probably use some suspension help. Stable loads were the answer for me, YMMV.
The way some people drive these days it doesn't matter what they do to their rigs, they're an accident waiting to happen. I work on the highways for DOT and have pushed my share of RV's off the road with a loader. Be patient, control your speed, and drive defensively -- you'll be okay. Just this week I assisted with the removal from the road of a nice, vintage Northland camper mounted on an '07 F350 SRW. He was towing a horse trailer with horses (DUH!). The rear end locked up and the truck jackknifed and fell on its side. The horse trailer stayed upright thank goodness. He was speeding, overloaded, and distracted. Ruined a really nice camper. I was impressed with how it held up though. Probably kept them from rolling.
Get some suspension help and don't set any land speed records. Try to outfit the camper with lightweight gear. And stay alert... NO texting and driving!!!
