Borrowed the van again and got 24 mpg (US) pulling the 2070 lb ForkenSwift about 230 km round trip to Ottawa and back for the annual EV Expo.
It's sort of cool to be able to match the EPA highway rating with that size of weight & aero penalty:
I took secondary roads, kept the speed between 70-85 km/h (43-53 mph).
Other techniques were: driving with load, some minor EOC up to stops/lights, driving without brakes.
My only other point of reference with this van was getting 26 mpg (US) towing the light (450 lbs ) sailboat & trailer last summer.
EDIT: I forgot... another point of reference I have is the test I did with my other brother's Ridgeline & trailer:
Honda Ridgeline MPG vs speed graph: fuel economy with & without cargo trailer