I tow with a 2011 Dodge Durango 5.7 Liter Hemi with factory tow package. It is the first year of the redesign. It tows great but I got it with room to spare: the tow rating is 7400 lbs with a payload of just over 1400 lbs and I am towing a 3800 lb high wall PUP with it. I get 22 mpg highway/18 city (not towing) and 14 - 16 mpg towing. But yes, the closer you get to tow rating in your TT weight, less you can put in the vehicle. And where I am right now, I do not take bikes - we take a second car when we want to do that.
HTT: "EscapeII" 2016 Shamrock 23WS (current)
PUP: "Escape" 2010 Rockwood HW 277 (gone)
TV: "Bruce" 2011 Dodge Durango V8 Hemi Crew
Just us gals (me, Sis and our daughters)
Traveled 19520 miles and 209 nights in 7 years and counting