US limitations on towable weights are ridiculous, probably driven by legal liability issues. My Kia Sedona is limited to 3500 ponds in the US. The identical vehicle in Europe can pull 3000 Kg (6600 pounds).
Many members of the UK "Caravan Club" pull 30-footers behind a Range Rover and sometimes behind what we know as the Land Rover Defender. We once met a man who had towed his trailer home (a 36' park model) from the north coast of Scotland to the Southampton area, behind a 1949 Morris Minor car which had a 990 cc L-head engine that developed 35 horsepower on a really good day.
Slow but sure, but they made it!
Frank and Eileen
No longer RVers or FR owners