aftermath wrote:
Turtle n Peeps wrote:
...
Sorry, you're not going to get 21 MPG average towing your high wall trailer.
UH, an Airstream is not a "high wall" trailer. An older Airstream is much lighter than the new ones today and a small older Airstream is even lighter.
I towed a high wall trailer and was getting around 11mpg. I traded it in for a newer Airstream what was 4 ft longer and a ton heavier, yes 2000 lbs heavier. I still get 11 mpg. The areodynamics make a huge difference just like driving into the wind instead of with the wind.
I accept the OPs position given he is on flat land with no wind. Still it is higher than we have ever heard. I got 17mpg on a leg through Colorado once with a tail wind. No, it wasn't a tail wind it was more like a tail gale, or hurricane! Was not a fun drive.
He posted his findings given his very special trailer and TV. There is no need to trash him. Calling him a liar is below the standards of this forum.
An Airstream is also NOT a "flatbed trailer" OR a "boat".
Many things do come into play, wind to your back and going DOWN hills and mountains AND ERRORS AT THE GAS STATIONS (gas station pumps sometimes are not as "accurate" as they should be) certainly CAN artificially inflate the mileage numbers.
But honestly, I do think the OP has made some error and it may be because they would have been traveling from higher elevations down to near sea level..
I have ALWAYS gotten BETTER gas mileage towing when I get near sea level and LOSE some mileage in higher elevations.
Putting ANY trailer behind a vehicle DOES severely reduce the mileage.
My 2013 F250 with 6.2 gets 15.1 empty, towing 6500 lb 26ft TT reduces that to 9.8-10.1.
The same vehicle with my 18ft 10K open flatbed with no load which weighs 2400 lbs empty on the SAME route drops the mileage to 10.8-11.2 mpg.
The four extra tires present a lot of extra rolling resistance which eats into your gas mileage.
Loading that same flatbed and towing with the same truck with a 3600 lb car on the trailer only reduced the mileage one or two tenths and that IS the same route.
Now, if the OPs shorter trailer only has one axle, they may not have lost quite as much towing mileage due to only two tires hitting the pavement, but I don't think it would not be all that much of a reduction in friction to be able to explain the 20 MPG..