Oh I have a 32 foot Passport 3220BHWE. It is about 7700lbs loaded (scaled)
We towed it with my buddies 3.5 Ecoboost to Sun Lakes Washington from Poulsbo...You can map it. Truck did fine. His is a crew cab so it has longer wheels base. That is a 4 hour trip, up and down Vantage, up over Snoqulamie and Tiger Mountain in the summer time. Truck didn't miss a beat, was better than my old 1 ton and just as good as my 02 2500HD.
He just wanted to see how well it would tow a larger trailer. He had a 24 footer and went to a 28 footer 3 years ago. No issues for him. To be honest I was curious too and I think the truck did very well.