Hi all
Thought I'd just add a bit
Been towing for 28 years and always find that a heavy foot = poor mpg whatever on the back.
We have Disco TDI 2.5 P reg ES model automatic, towing Senator Wyoming 2006
On the M'way at 55 - 60 we get 20 mpg ish while towing.
Solo at 65mph we get about 24mpg...