Just back from picking up a 16' Scamp
in Mineral Wells, TX and pulling to Austin and then to Mobile, AL.
1st afternoon (overnight in Lampassas) and then to Austin averages 28 MPG with our 2009 Jetta Sportswagen TDI with the DSG automatic. This was on Texas backroads in the hill country 58 - 62 mph.
Later from Austin to Mobile against a head wind driving ~ 65 mph we got right at 25 MPG on the interstate.
This is reading from the MFD in the car which is a little optimistic in my opinion.
The JSW towed great and had plenty of power and the DSG transmission behaved itself quite well. All together a great combo. The trailer was a little light
since most of the appliances had been removed, but there was a window A/C and dorm refrigerator
in th camper.
We plan to renovate the camper and rig it to meet our needs and keep it as light
Towing with the VW was a no hassle experience and the mileage was excellent.
When you look at the Diesel mileage you need to factor in the higher fuel cost and weigh it against the better torque. Torque wins, by the way. Also when you compare our mileage with other VW TDIs our wagon has never gotten much over 40 - 42 MPG on our trips and has (now) 211,000 miles +.