I am close to purchasing a 2020 Keystone Cougar bunk house (29BHSWE) and will be pulling it with a 2018 Ford Expedition Limited Max. Tow capacity of 9000lbs. Weight of trailer is 6,810 dry and GVWR ...
It is simply not a good idea to be over, but tow with what you have and see how it goes. Once you’re in the wind, or a semi passing you, you’ll know. Once you have to go through a mountain pass with steep upgrades and downgrades your mind will be made up. Your not so far over it’s dangerous as long as you give yourself some room and time. For me it took several thousand miles of varied terrain and I knew.