drag reduction for 5th wheel

[wjpatton]

Anybody have some exprience with aerodynamic wing on top of the truck cab and improved mileage pulling a 5th wheel? Looking for real world data before forking out some money.

 

[DonTX]

Many of the Winter Texans down here have tried them, and report not one bit of help.

 

[WestTN]

I don't have experience with a fiver, but I did in the past pulling my 29' conventional behind a van. I built my own wing and made it adjustable. Using a vacuum gauge on the gasser, I slowly adjusted the wing on various trips until I hit a sweet spot. Sweet to the tune of almost 25% better mileage.



Then I heard of an easier way to adjust it. Tie a ribbon long enough to reach the roof of the trailer to the wing and take it for a drive. Adjust the wing until the ribbon just barely lays on the trailer roof while moving.



For my rig described above that sweet spot was in a plus or minus range of about 3/8"elevation at the back of the wing.



If your wing is much more than 6 or 7 feet from the trailer, you will only be creating turbulence.

 

[jelag]

After spending some time with a engineer and having several hundred hours with a chassis dyno I have to put my 2 cents in...

A good mechanical engineer can plot a graph for you based on weight, acceleration, wind resistance and through this formula predict with in 5% of a vehicles mpg... .

I would like to add that my wife gets better MPG than I because she drives slower and accelerates slower... and VW is looking at removing out side rear view mirrors and replacing them with a monitor because of the change in wind resistance.....

I do not believe, after what I've learned that you could achieve more than a 1-3% increase in fuel economy over the current bubble used on modern 5er's...

I own (2) 5er's as well as several work trailers... . work trailers up to 22K lbs... let's cover the 5er's only... one is a mid 90's and weighs 10,500 lbs and has a very simple slanted front, the second is an 06, weighs close to 13,000 lbs and has a nice bubble... . (better design). The 06 tow's better and we get the same fuel economy with the newer trailer. The newer trailer is 14" taller and several feet longer than the old trailer.....

So if you have an older trailer you might maybe see 3-5%... .

Thanks for listening.....

 

[GaryOwen]

I tried an Aerotravel wing on my 95 while delivering 5th wheels and travel trailers. I agree with Jim that the advantage is minimal and is not worth the investment or hassle.



I saw about 0. 5 mpg increase on 5th wheels (05 and 06 models). However, I saw about a 2 mpg decrease when not towing. The Aerotravel could not be tilted down when not towing. Found it was not worth the effort.



Also, I also tried the wing with travel trailers and saw no change in fuel mileage, but did see some increase in stability from side winds.



Hope this helps.



Gary

 

[Ram4Sam]

I had one on my 91' with a fifth wheel. Mileage didn't change much if at all. But they do a great job keeping the bugs off the front of the fifth wheel.



Sam

 

[steved]

I'd be looking more at the tires (rolling resistance) and bearings (either make sure you got the proper grease or swap to a lube oil type)...

Wind resistance is a hard one to nail... I will however say that I get better mileage towing a 24-foot 5vr than toting a 8-foot slide-in camper around...

steved

 

[DMcGalliard]

Not worth the effort

I pulled my Coachman 5th 8k miles from NC to the west coast, north to Oregon, east across ND and back to NC. I had the wing and I tried it in all positions and could not find any measureable improvement in the MPG. So I took it off and put in the barn. Spend your money on a lotto tickets.



Hope this helps,



Dave Mc

 

[Okie-Go]

I have a Taylor wing. This is the 3rd truck it has been on. I can tell the difference when not using it. Look at the semis, most of them have one for one reason, they help. It will take a while and a lot of pulling to get your money back as they are expensive. I haven't had a chance to check on new truck but the 01 added a mile a gallon while towing. Lot's of folks say they can buy lots of diesel for the price of one. With fuel going up they are able to buy less diesel and I still have the wing!

 

[rluft]

I have seen advertised a wind deflector that is self-adjusting, I understand it can be laid flat when runnig empty. Anyone using one and have any opinion?



I also have wondered about the underside of the trailer. Mine is not covered so the tanks and the cross ribs are all exposed. The bottom of the trailer is a good 2 feet off the ground, creating a good chance for air turbulence. I have considered covering mine but have yet to do it.

 

[rweis]

I have a friend tht gave me a wing (ie no cost). I have driven it for 3 years, have a high profile 5er 13k.



Only difference I see is it keeps the bugs off in the foot print of the wing. My wing is smaller than the front of the 5er. Eventhough the wing is angled at the ends of the wing to supposedly get air to go around the front of the 5er it does not. Bug pattern verifies this.



Slow down to get better mpg. When towing I tow (5er = ALFA Ideal, high profile, 13k, 36') at 2000 rpm (62 mph / auto transmission / 4. 10) and get about 12mpg in flat Florida. I got the best mpg last summer (trip to Arkansas 1000 miles 1 way) after installing a bed tank.



I think because I slowed down to 60 mph and did not have to stop for fuel. I refueled when I stopped for the night. BTW, it was a MUCH easier drive on me because of not having to plan fuel stops, and casually cruising along, much much less stressful drive. Just STAY out of the way of the rest of the traffic.



Bob Weis

 

[DonTX]

I wish I could slow down, I get 14mpg towing my very tall Avion, gross at 20k on the road, driving 70-75. The truck has a sweet spot there, under 2000 rpm.

 

[RVTRKN]

I wish I could slow down, I get 14mpg towing my very tall Avion, gross at 20k on the road, driving 70-75. The truck has a sweet spot there, under 2000 rpm.

Ya, I know that sweet spot as well, too bad the CHP are lurking out there as well. California speed is 55 , and for the most part they leave you alone but I hate the feeling when you pick one up on your tail.

 

[surfbeetle]

Okay, out of curiosity, along the lines of wind drag does anyone have experience with a Titanium Fifth wheel? They have that cab over aerodynamic design in the front. With my current truck's sleeper cab, I can't use one but they claim better fuel economy with that.

 

[donnandon]

Okay, out of curiosity, along the lines of wind drag does anyone have experience with a Titanium Fifth wheel? They have that cab over aerodynamic design in the front. With my current truck's sleeper cab, I can't use one but they claim better fuel economy with that.

We just got a Titanium 34E39QS last year. I think it actually tows much better in the wind than our old travel trailer. I can't compare to another 5th wheel for wind drag and mileage, but it seems to handle really well, even with strong headwinds.

 

[Jack in Alaska]

I personally think that a grown man has disallusioned himself if he believes he gets 14 mpg towing a tall 20k pound 5th whl. at 70-75 mph. That just ain't going to happen.
But have a safe trip doing it.

 

[tom sweeney]

..... yup,i tow a Holiday Rambler 27' 5'er thats 10k or slightly higher... . and with a wing,i could only approach 14mpg falling off a cliff!!!:-laf

the wing does help with the bugs,but as far as i can tell,thats about it.

i tow from Maryland to Nevada each year for May Madness,and i usually use 10mpg for calculating how much money will be required for the trip... . i have gotten 11-11. 5 mpg on a rare tankful..... very rare indeed... if i could run at 60-65 without head/side winds,pehaps i could do better than 10mpg... but ABOVE 65mph with a high profile 5'er mileage WILL suffer..... as stated above,the biggest secret to increasing mileage is in your right foot!!!!

... ... ... ... ... ... ... . JMHO... ... tom

 

[Champane Flight]

12 solid...

Pulling 30' Hitchhiker with 17' boat behind, solid 12mpg. I do like the looks of the new Titaniums, all reports say they pull much easier than standard fifthwheels.