True or False?

[crokett]

True or False? Having the tailgate down on a truck increases fuel efficiency.

BT3Kers as a whole are a smart group so I expect most of you to get this. Please just answer the poll (no comments) and I will post the answer in a few days.

[gjbivin]

They tested this on Mythbusters. I won't give away their results just yet.

[mudder]

Watch Mythbusters..... They proved that tailgate up causes a turbulance bubble in the bed that reduces drag.

http://kwc.org/mythbusters/2005/11/e...s_cures_f.html

[jAngiel]

I have always heard that the best way to reduce drag was to get a cover for the bed, something I just can't see me doing anytime soon. It's too easy to go buy something and toss it in the bed without having to roll up a cover or pop it up. There are a lot of variations of the covers around but when I want a load of dirt I don't want to have to screw around with a cover. For me the truck is a TRUCK, meant for hauling.

[Wood_workur]

I have always heard that the best way to reduce drag was to get a cover for the bed, something I just can't see me doing anytime soon. It's too easy to go buy something and toss it in the bed without having to roll up a cover or pop it up. There are a lot of variations of the covers around but when I want a load of dirt I don't want to have to screw around with a cover. For me the truck is a TRUCK, meant for hauling.

no, best way to reduce drag is to buy a sedan...

[crokett]

Please just answer the poll (no comments) and I will post the answer in a few days.

Oh well. Since the answer was already posted I will 'splain.

Having the tailgate up keeps air in the bed. This produces an effect similar to a tonneau cover - the air flowing over the cab keeps moving over the top of this still air. If the tailgate is down you lose this effect, increase drag and actually lose efficiency, 5-7% are most estimates.

If you remember as a kid if you remember riding in the back of a pickup, the air is relatively calm in the bed - much more so than you'd expect.

[Otter]

The best way to reduce drag..........is not to put on the dress

[Ken Weaver]

My truck doesn't go fast enought to worry about aerodynamics :-)

[BobSch]

no, best way to reduce drag is to buy a sedan...

Or a Porsche.

[Tundra_Man]

When I got my last truck, it came with a topper. After about six months, I realized I didn't like having a topper (as James mentioned above, a truck is a truck) so I removed it. Amazingly, my gas mileage improved by about 3 mpg!

[ewingda]

A truck is really a brick with wheels when it comes to aerodynamics! If you want less drag - dont drive it!

FYI - I have a Honda Accord V6 and Honda Ridgeline. Similar engines - huge fuel difference!

Dave

[bigsteel15]

the best way to improve fuel economy in your truck is to only drive it when you need to haul something.
The rest of the time, drive a VW.
My 87 GTI has over 500,000 miles on it and still going at 40 MPG

[cwsmith]

Hmmm, interesting..... but does the air bubble leak out when the truck bed has rust holes in it??

CWS

[Texas splinter]

Consumers Union ran extensive tests on this subject in the mid 90's when gas prices spiked for one reason or another.
The tested trucks with and without the tailgate open, bed cover on and off, and with and without a cap on the bed.
End result was that the stock condition, tailgate closed, got the best mileage.
But...The difference between highest and lowest milage was ess than 2 MPG.
They talked to the design engineers at Ford, GM and Dodge and found out that, on trucks built prior to about 1990, the tailgate down may improve MPG, but starting with the 90 modles, the trucks were tested at the NASA wind tunnel in VA. It became available to them and they started using it.
As has been stated here, the truck is designed to maintain a "bubble" of air in the bed that passes the wind over the bed and tailgate. Anythin tat disturbs this bubble will lessen MPG.
I drive a 2001 F250 Superduty diesel 4WD and since fuel wint up, have slowed 5MPH, to 65 or lower. My MPG has gone up 2 to 4 MPG, epending on highway or town driving.

[Russianwolf]

Hmmm, interesting..... but does the air bubble leak out when the truck bed has rust holes in it??

CWS

I bet that rust holes would have an effect on the test.

I don't worry about milage in my 36 year old Jeep pick-up. It sucks and I know it, but since I only paid $600 for her, it'll take 10 years of driving her full time (which I doubt I will) to see a downside. I only drive her to and from the train station (about 4 miles) and on errands on the weekend. I'm betting I'll spend $500 a year on gas.