Truck Mounted Wind Deflectors

[timandsusan]

This maybe an old topic but I did not find anything on a search. As I was leaving Las Cruces, NM, today, a fellow RVer (SOB)said his wind deflector increased his mileage by 2 miles per gallon. He had 3/4 ton with a 5th wheel about 36 feet with 3 slide outs.
Question--Any MOCer have experience with these deflectors?? With the price of diesel going to the sky--it is time to look at everything.

[TLightning]

I'm on another RV forum, the consensus there is they are no help...in fact, they won't pay for themselves.

[Hemlockusa]

Tim, I am not going to call the man a FIBBER. However there have been numerous studies done on this subject. The majority of the studies concluded that the savings as a result of the deflector was so small, the only ones that would benefit from them would be truck fleets and then only after many many years of driving. The benefit was only fractions of a gallon then. I think I do recall one study that concluded if the cost of the deflector was $700.00 it would take 11.3 years to break even. I use to fish a lot and at the time (In my young Days) the fish were all bigger and weighed more, as you get closer to the dirt nap, those figure's don't really matter anymore!!!!! 2 miles to the gallon????????????????? BRANSON IS GREAT IN 2008

Safe Travels John

[richfaa]

The turbulence is in the pickup bed around the nose of the camper. Those truck top deflectors work fine on the 18 wheelers along with the other side deflectors. I think the claims of increased MPG from those who have them is because they paid big bucks for them..so they are going to work???? Just my opinion...

[stiles watson]

I will add my no vote to the very ugly deflectors, for the same reasons.

[ols1932]

I had one. Used it several years and finally threw it in the trash. Usually, the only ones who say they help is because they want to justify the cost. Mine is in the trash dump in Cedar Rapids, IA.

Orv

[dieselguy]

I had one on my previous truck that was a 460 gasser. I got it second hand, so I didn't have much invested in it. Did it improve fuel mileage ... not that I could measure. Did it do anything measurable ... it kept most of the bugs off the front on the fiver. Even folded down, I could not drive in my garage due to clearance with my 1 ton. Although the company advertises improved mileage ... it's a relative of that magnet that goes around the fuel line that's also supposed to improve mileage. Slow down to 60 - 63 mph and you'll see better fuel mileage at the price of just a little more windshield time.

[sreigle]

I have no firsthand experience but the couple of tests I read indicated they can increase mileage but ONLY if they are located in the proper location on the roof and have exactly the correct angle. And further, the only way to properly set them on private vehicles like ours is using a wind tunnel.

Miracle mileage improvers always improve mileage for awhile simplay because the owner is going to driver very carefully to see how good mileage he'll now get. Chances are he'd do just as well without the deflector if he'd always drive that same way. Just speculation but that's where I'd put my bet.

[skypilot]

As I read on RV net last summer - the wind deflector is good for one thing - moves where the bugs hit the 5er up to a higher level!! To get any really measurable improvement we would need to do as the large semi's do - have a wind deflector that goes as high as the rig we are towing, and then have the fairings around the sides and top to keep air spillage from filling in the void between our cabs and the front cap of the trailer. The air turbulence trying to get down in there is horrible and creates significant drag. Costly to build, install and maintain. It would take years to recoup the costs, if you even could. Best to just slow down a bit.

[Dave e Victoria]

The worst part is if you wear one it's like saying "Look at me -- I'm a sucker!"
Dave