Aerodynamic Trailer Drag.

[bbuton]

I started pulling a small enclosed trailer, 6ft wide 6ft height, and 12 ft long. I noticed that at 75 to 80 mph my fuel economy dropped 4 to 5 mpg even when the trailer is empty. Does anyone have any experience in setting up a truck and trailer so that it doesn't take such a fuel economy hit? For example, are the V-Nose trailers alot better or just marginally better than the "flat face" trailers. Does a camper shell make any difference? Thanks for any ideas.

 

[sewman]

I have towed alot & thought 11-12 mpg was pretty bad @ 85mph w/a 12" tamden trailer but I had a cap on my truck & supposed this helped. I now have a 16'v-nose that pulls easier than the 12' on the flats even w/more weight. So if you get a chance f/a v-nose I'd say get it.

Bob

 

[GAmes]

A V nose trailer would be better, a camper top would be an improvement too, but the best way to improve MPG (and it is free) is to SLOW DOWN!!! Drag increases expodentially with speed and that is what is killing your mileage. A 300 mile trip would take about 30 minutes more at 65 , about as long as the extra fuel stops you have to make driving at 75.

 

[icarus33]

In October I pulled a 8'X16' Wells Cargo trailer from NM to WA. Was unloaded going up, filled to the ceiling of the trailer and the back of the truck on the way back. I have a snugtop shell. Mileage up was 11. 95 and the return was 10. 8. This was running @ 70mph on average. The V nose would likely help some, but for the trailer I bought, it added about $900 to the cost and that was at this Springs steel prices, it has all gone up more now. The biggest drag however, is on the backside of the trailer, and there is not a whole lot you can do about that.



ic

 

[MicroOutlawRacer]

One word AirTab http://www.airtab.com/ They work great and actually do help with fuel economy and make the trailer a little more stable.

David

 

[OTRPU]

My experience, GAmes knows it all when it comes to getting better mileage when a towin. Mileage is directly proportinal to the square of the pressure you exert on the accelerator.



Cheers,

Steve J

 

[pwerwagn]

I have a 24' enclosed car hauler, and it has a sort of angled front top edge. When full, it weighs about ~7K. My mileage is excellent. We dont have to many big hills here in NM, but some decent ones. I usually get about 16mpg towing it 70-75mph. not to bad at all. I dont have a shell.

I towed my big power wagon (7" lift and 40" tires) on a trailer this summer and still averaged 14. 5 running 70, but the wind drag is probably less than an enclosed traielr would be.

Air tabs do work.

lower speed does work also.

 

[continentaldrifter]

SLOW DOWN!! whats the rush. Just like Games stated 300miles is extra 30minutes @ 65mph. IT WORKS and its free

 

[Eric_77]

A V nose trailer would be better, a camper top would be an improvement too, but the best way to improve MPG (and it is free) is to SLOW DOWN!!! Drag increases expodentially with speed and that is what is killing your mileage. A 300 mile trip would take about 30 minutes more at 65 , about as long as the extra fuel stops you have to make driving at 75.

Actually 37 minutes but the more intriging issue would be the truck that would need a fuel stop in a 300 mile trip. I guess you must have been thinking of a Ferd.

 

[pwerwagn]

I think he meant that driving 75mph, you will spend as much time making fuel stops as you will loose driving 65 and saving the gas.

 

[GAmes]

Yup!!

I think he meant that driving 75mph, you will spend as much time making fuel stops as you will loose driving 65 and saving the gas.

That is what I meant. bbuton didn't give any mileage figures, but if I was pulling that trailer 75 I'd be getting about 8 mpg. With about 33 gallons of usable fuel in my stock tank that would give me a range of 264 miles. Pulling it at 65 I'd be getting about 13mpg, a range of 429 miles.

 

[jetenginedoctor]

FWIW. . .



A trailer with a rounded nose cone (i. e. Wells Cargo) is far more aerodynamic than a trailer with a V-nose shape. A V-nose is only very slightly more efficient than a square nose trailer.



Take a look at what shape the fuselage on a jet aircraft is up front. A pointy, V-nosed shape is only desireable on a supersonic vehicle, and only because of how the shockwave propogates across the leading edge at trans-sonic and supersonic speeds. The V-nose is nice in that it gives you a good bit more interior cargo volume, but it won't do much to improve towing fuel economy.



BK

 

[Spyke]

I agree slow down I recently did a trip from MD to CA and back and ran a couple of tanks at 1950 RPM 2050 RPM and 2150 RPM basically 65 70 and 75 MPH. the difference in distance and time involved and the cost was interesting ex 70 mph equals 700 miles in ten hours 75 MPH equals 750 miles in ten hours but that distance cost me an average of $ 14 dollars for the 50 miles, so I travelled at about 2K RPM.