Hello Allan D, Based pulely on your weight figures and your prefernce to hold to about 85%, you are limited to mainly large cars/estates from the upmarket manufactures. However noting your aversion to 4x4's and looking for a large estate, then in addition to the Volvos, and Mercedes have you considered the MPV's from Citroen/Fiat/Pergeot, Ford/Seat/Volkswagen, and of course Renault. These are all available in Diesel, with good kerbweights and healthy towing margin, not to mention the cavernouse boot space (if you ignore the thrid row of seats.