Mondeo Estate 2006, 2L diesel, managed 39mpg whilst towing my Avondale caravan from the Midlands to the Cumbrian coast.
Replaced with the 2.2L diesel estate and it did the same journey and back on a single tank of fuel.
Trip to Cornwall not towing with an average mpg for the 300 miles of 58mpg, it was looking close to 60mpg until we hit the Newquay area. Impressed for such a big car.
And no it wasnt at 40mph either :). 70mph on cruise control for most of it.
Our ancient Volvo is quite good too, for such a big heavy car. 38mpg average general use, 50mpg solo on a long run, and around 38mpg on a long run with the caravan on the back. It's a 2.5 litre diesel automatic, and it's 18 years old. I don't tend to hang around either!