It is easy to overlook the Land Rover LR4 with so many typical options available from Ford, Dodge, Chevy and Toyota. I believe it may have all of the features you are looking for. The LR4 has a locking center and rear diff with selectable terrain response. Three rows of seats that fold flat into the floor for a level loading area. It has won tow vehicle of the year in the UK several times. It has a 7,700lb towing capacity with integrated trailer sway assist and towing back up camera with a hitch up assist feature. Auto leveling air suspension on all four corners gives you a fantastic ride and levels your trailer automatically. You will not win any fuel saver awards, as the truck does not get good gas mileage - but that is expected from a truck that weighs just shy of three tons. We have been towing with one for years (actually, an LR3 which is the previous model) and I can tell you that the vehicle is a towing machine that inspires confidence. When not performing towing duties, it is my wife's daily driver.