Community Forums

Denlor · 01-01-2013, 01:49 PM

Does anyone out there use a wind deflector mounted on the tow vehicle? We are going to be doing more travelling than usual and are thinking about one for our Suburban pulling a 33ft TT. Would like to hear any replies as to the advantage or if they are a waste of money. Thanks

Bigg-limo · 01-01-2013, 03:50 PM

don't know from my own personal experiences,...but know people that have them, and they all have mixed results.

drakethib · 01-01-2013, 04:04 PM

Was interested in this myself.

Not sure what they cost though

TXiceman · 01-01-2013, 06:23 PM

Tried one when we had a TT. The only thing I could see that it did was keep some of the bugs off the front of the trailer. No change in handling or fuel economy. I vote to save your money and send it on the trip.

Ken

Denlor · 01-01-2013, 07:05 PM

Thank you for your feedback. I have been confused about the advantages and now am sure I will not buy one as they are pricey and maybe not worth the cost

Capt Steve · 01-04-2013, 06:46 PM

I installed my wind deflector last spring and field tested it thoroughly through October. My truck is an 2006 F-150 Scab 5.4L with a Leer Shell. The trailer is a 2008 22', 5600# GVWR Pioneer Spirit 18CK.

"Yes!" they work. I consistently have gotten a 1.5 to 2.0 mpg increase since installing the deflector. It helps that mine is located at the aft end of the Leer Shell as moving them closer to the trailer enhances their effectiveness. I spent $377 delivered to my door(From Icon Direct), and at $3.50 a gallon it will have paid for itself in less than a year.

Here is a picture of the truck and trailer. Note that the angle of the wind deflector in this shot is way to steep. The proper angle is for the deflector to be aligned with the top leading edge of the trailer.

Once I got the correct angle I saw an 8%+ increase from 11 to 12.5 in mileage {along with the bugs disappearing from the front of the trailer}.

We average 12.5 mpg and that is camping throughout the serious mountains of Arizona. We spent most of the summer, 30 days over the course of 7 trips, between 6,000' and 9,000'.

If you do not have a shell (you really should get one but I digress),

placing the deflector on the roof of the cab will work but probably deliver slightly less of an improvement. The closer to the trailer you get the wing the more efficient it becomes.

For the record I drive the speed limit or less and am well under the max weight ratings for my rig. If you are looking for mileage improvement for less money get yourself a Scan Gauge (about $150), and let it teach your right foot how to drive more efficiently. The first trip with the Scan Gauge improved our mileage from 10.3 to 11.3 or roughly 9%. By putting the SC together with the wind deflector I have increased my mileage by approximately 18%.

TXiceman · 01-04-2013, 08:30 PM

The wind deflector we tried was on a Chevy Blazer pulling a 20' TT. So the deflector was mounted at the rear of the Blazer, much like over the cap. We also pulled a Avion silver trailer with a pick up and we did see an increase in flue economy a bit over 1 mpg with the cap installed.

Did you try the wind deflector with and without the cap?

The wind deflector on the Blazer did keep the front of the trailer pretty bug free though.

Ken

Capt Steve · 01-05-2013, 09:16 AM

I already had the Leer when I got the deflector so have never run it on the top of the cab. I spent quite a bit of time talking to the folks at Icon Direct and they are convinced that the closer to the trailer the greater the effect. It takes about two minutes to put it on/off and when we leave the trailer we just put the deflector inside until the next trip.

Getting the angle right is also crucial for optimum performance. Half way through our first trip with the WD I noticed we were still getting bug strikes on the front of the trailer. I adjusted it another 10 degrees and the mileage jumped almost one full mpg on the Scan Gauge. Once I got it right (and the bugs went away), I marked the angle and have left it there with good result.

We are planning an extended trip of several months for this coming spring and summer and an extra couple of mpg will be nice. Picked up our Golden Age pass last month as well. We average about 6,00 miles a year towing so it only took one year to break even on the WD purchase. From now on we get the fuel savings for free. I'm surprised you don't see more WD's out there.

elkhornsun · 01-09-2013, 05:46 PM

Steve's setup shows the best scenario where the deflector is relatively close to the trailer and the trailer roof does not extend past where the new wind flow should be directed past the truck with the deflector in place. It would be more difficult to get this type of positioning with a 5th-wheel trailer with their much higher profile. I would be investigating a fiberglass cap that could be attached to the front of the 5th-wheel to provide a better profile. A company that makes them for commercial trailers is Nosecone at Air Deflectors For Trucks | Air Foil Nose Cone | Aerodynamic Semi Truck & Trailer Wind Deflectors.

NoseCone Pull Trailers

The aerodynamics of a trailer are also affected by its squared off rear end. Better is a tapering off as with the old French Citroen automobiles and the Prius. There are trucks pulling trailers where a rear skirt has been added on to correct this in part.

When towing a trailer the truck has to overcome rolling and wind resistance and do work to lift the weight when going uphill. The right tires and oil lubricated axle bearings and less weight in the trailer can all help with rolling resistance. Reducing the cargo load in the tow vehicle and trailer will also reduce the energy used to accelerate the trailer and to take it up hills. The deflectors can help with wind resistance.

The maximum theoretical overall gain for tractor trailer rigs with improved aerodynamics (as researched by NASA and others using wind tunnels) is 11%. Expect less than half this as you are not able to modify the side spilling or air or rear end dynamics or the undercarriage turbulence and other factors, only the front end wind resistance.

Whatever you do I would put in the might help can't hurt category.

bdwillie · 01-09-2013, 06:00 PM

We installed one when we bought our first fiver, it had a pretty flat nose. Got one that went in the stake pockets of the truck. We had an increase in gas mileage that was quite noticable, BUT with the new cruiser we just got, we tried it with and without and there wasn't any differance with or without it. The cruiser is so rounded in the front it made the deflector not needed. It's sitting in the shed waiting for the next 5er.

So I guess I'm saying, depends on the trailer nose.

caissiel · 01-10-2013, 04:41 AM

Quote:

Originally Posted by bdwillie

We installed one when we bought our first fiver, it had a pretty flat nose. Got one that went in the stake pockets of the truck. We had an increase in gas mileage that was quite noticable, BUT with the new cruiser we just got, we tried it with and without and there wasn't any differance with or without it. The cruiser is so rounded in the front it made the deflector not needed. It's sitting in the shed waiting for the next 5er.

So I guess I'm saying, depends on the trailer nose.

I agree most newer 5th have greater front caps. Eggshape is best as I have noticed on ours.

7k axles with load G tires for me are a must at 110 lbs inflation. Its a world of difference from 65lbs.