Airstream Caravel towing mpg question

[ohpoppy]

I just bought a 17' airstream in OK city and drove it home to SC. I got 13 mpg leaving Okc (2005 Volvo V70 tow veh)which is very poor but as I continued on mpg improved dramatically, gradually. When I reached SC. I was getting 21 mpg. Altitude?? or something else caused the difference. I wonder if it took 1000 miles for the cpu to re-calibrate the best fuel mixture for towing 2500 lbs and it took 1000 miles to do it. Has anyone noticed the tow vehicle getting improved performance after driving a while in the same altitude? I wonder if disconnecting the battery before towing will cause the cpu to immediately re-calibrate or faster then just hooking up and going. maybe its just altitude! car gets 31 mpg not towing on hwy.

[Gdetrailer]

Slowmover wrote:
Put that Caravel or its more modern equivalent Airstream behind a diesel Jetta from just a few years ago, and, at under 100 km/hr see almost 30-mpg US.

The penalty is usually 40%. Weigh the TV solo (loaded for camping, with pax and full fuel) and at approximately 60-mph the fuel burn will see a penalty of 40%. 1968 or 2018.

Aero is what matters most. But with two lightweight vehicles and a turbocharged Diesel engine, you’re going for a numerical high.

With my four-ton CTD Dodge and similar weight aero 35’ TT, “the penalty” brings me to 15-mpg. Just as predicted.

Meh.

My own experience towing a full height TT vs a open flatbed trailer shows otherwise.

Yeah, I USED to think the way you think.

If what you say about "aero" mattering then I should have barely seen a difference in my non towing mileage vs empty flatbed trailer towing mileage.

The fact that a 2400 lb empty flatbed trailer resulted in only a few tenths better mileage compared to my 6500 lb full height TT.

The flatbed trailer has no "front" and only short 2 ft open slat sides and a dove tail rear deck..

Applying your logic, I should have lost .1-.2 MPG with that trailer, it was considerably more..

The only reason I can figure out is the ROLLING resistance of FOUR EXTRA tires hitting the road is a major factor, more than "aero".

Weight isn't much of a factor, in fact I have had well over 2500 lbs in the back of my truck, with not much more than 1 or 2 tenths of a mile mileage difference between empty and loaded.

[rbpru]

I will admit, when it comes to my PUP, I get really good gas mileage, it sits lower than the truck and cost me about 2 mpg.

That certainly is not true with my TT.

But I never question another person's gas figures. If they believe them, and it makes them happy; whether I believe it or not makes little difference.

They are paying for their gas not me, so why should I care what mileage they get.

I get 10 mpg average, that is all that matters to me.

[Slowmover]

Put that Caravel or its more modern equivalent Airstream behind a diesel Jetta from just a few years ago, and, at under 100 km/hr see almost 30-mpg US.

The penalty is usually 40%. Weigh the TV solo (loaded for camping, with pax and full fuel) and at approximately 60-mph the fuel burn will see a penalty of 40%. 1968 or 2018.

Aero is what matters most. But with two lightweight vehicles and a turbocharged Diesel engine, you’re going for a numerical high.

With my four-ton CTD Dodge and similar weight aero 35’ TT, “the penalty” brings me to 15-mpg. Just as predicted.

[Gdetrailer]

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..

[mountainkowboy]

ohpoppy wrote:
hey soundguy.. stop acting like such a jerk. I'm telling the truth and my iq is much higher then average. I started this discussion with the hope of understanding this better, not to misinform. I am an honest person.

He has no choice...he has to troll its in his blood

[Passin_Thru]

If he went across I40, No part of Arkansas is Mountains. There are about 4 hills in Western Ar. I get 9.8 at 67 MPH with my Arctic fox 31W. Thats from Va to NM to Co and back. Can't get more. I don't believe anyone gets 20 MPG towing a trailer and I'd like them to come and I'll do the test. BHP (Brake Horsepower) takes so much fuel to produce and there is a formula for it. It's called Specific fuel consumption and we use it fo calculate fuel burn on aircraft.

[dodge_guy]

My brother has a 2500lb PuP and tows it with a minivan that gets 25mpg not towing. towing the PuP he gets 12-13.

No way is the OP getting 20mpg towing a tall trailer!

[FF286]

I don’t understand why because you mileage sucks anyone who gets better either can’t do simple math, or tell the truth. I’ve had 5 different campers over the years 4 being 5ers. The first one I would get 13-14 mpg, a 87 Starcraft low profile, the next was a 97 sandpiper I would get 7-9. Same truck. The other 2 have been around 11. With the mind set of some of you I assume I actually got better mileage with the 97 since you get 10-11. the trips I figured 7mpg must have been a miscalculation I guess.

[rbpru]

Personally I tell folks I get 10 mpg towing, 15 mpg around town and 20 mpg on the highway with no TT.

If someone is getting 20 mpg plus towing, fine for them. I prefer to let them chase their tails, until they realize that over the long haul; they get 10 mpg plus or minus 2 mpg. like everyone else.

Also, all thing RV considered, gas mileage is way down the list. "It is what it is", to use an old cliche.

Safe travels

[aftermath]

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.

[SoundGuy]

GrandpaKip wrote:
ohpoppy, please do keep us informed. I would be very interested to see if you can duplicate those results.

Well hopefully he will as certainly no one else can! :W

[GrandpaKip]

SoundGuy wrote:

ohpoppy wrote:
hey soundguy.. stop acting like such a jerk.

Thank you for that. :W

ohpoppy wrote:
I'm telling the truth and my iq is much higher then average.

Doesn't seem so. :R

ohpoppy wrote:
I started this discussion with the hope of understanding this better, not to misinform. I am an honest person.

Your methodology is flawed. No one gets the kind of fuel mileage you're claiming while towing ANY full height trailer. NO ONE. :S

Well! That certainly settles it.

ohpoppy, please do keep us informed. I would be very interested to see if you can duplicate those results.

[ohpoppy]

I'll leave you to consider all of this, I'll put it to the Volvo people to chime in.

[SoundGuy]

ohpoppy wrote:
hey soundguy.. stop acting like such a jerk.

Thank you for that. :W

ohpoppy wrote:
I'm telling the truth and my iq is much higher then average.

Doesn't seem so. :R

ohpoppy wrote:
I started this discussion with the hope of understanding this better, not to misinform. I am an honest person.

Your methodology is flawed. No one gets the kind of fuel mileage you're claiming while towing ANY full height trailer. NO ONE. :S