Mpg-tailgate Up Or Down?
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Junior User
Joined: Dec 2003
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Mpg-tailgate Up Or Down?
Recently I saw an episode of the TV show MYTHBUSTERS and I found it very informative. They took two identical F150 trucks and put in the exact same amount of fuel. They drove them on cruise at 55MPH until the trucks died. The truck with the tailgate up went 30 miles further than the tailgate down truck. They had some diagrams that were supplied by FORD that show why this happens. As far as I can understand with the tailgate up there is roll of air behind the cab which the air coming off the roof flows over it and the tailgate. With the tailgate down there is no roll of air and the air just comes down onto the bed causing drag. If you get a chance catch the show. JUST A LITTLE INFO, FISHEAD
Senior User
Joined: Jan 2004
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From: Southern USA
i saw that, i think it was a very accurate demonstration. there was also an article posted (a link) in this forum not too long ago, where some other folks did a silimar type test and also proved this out to be true. i'm a believer now, but before these recent "tests" that i've seen or read about, i would have argued with anyone to the contrary. i'm sure theres exceptions like if you have a bunch of stuff or junk piled in the bed, this would create some unpredictable results. BTW i really like the mythbusters show.....cool stuff they do!!
Fleet Mechanic
Joined: Nov 2005
Posts: 1,847
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From: Lehigh Valley, Penna.
Originally Posted by fishead
Recently I saw an episode of the TV show MYTHBUSTERS and I found it very informative. They took two identical F150 trucks and put in the exact same amount of fuel. They drove them on cruise at 55MPH until the trucks died. The truck with the tailgate up went 30 miles further than the tailgate down truck. They had some diagrams that were supplied by FORD that show why this happens. As far as I can understand with the tailgate up there is roll of air behind the cab which the air coming off the roof flows over it and the tailgate. With the tailgate down there is no roll of air and the air just comes down onto the bed causing drag. If you get a chance catch the show. JUST A LITTLE INFO, FISHEAD
I assume they swapped which tailgate was up/down and repeated the test with the same results?
I don't doubt the airflow results supplied by Ford but the shows tests are often less than scientific.
Logistics Pro
Joined: Jul 2002
Posts: 4,821
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From: South Dakota
Originally Posted by 53deere
Identical trucks? Verified HP and fuel consumpsion rates on a dyno?
I assume they swapped which tailgate was up/down and repeated the test with the same results?
I don't doubt the airflow results supplied by Ford but the shows tests are often less than scientific.
I assume they swapped which tailgate was up/down and repeated the test with the same results?
I don't doubt the airflow results supplied by Ford but the shows tests are often less than scientific.
They didn't swap truck end gate positions, but they did put a replica model in a water tank and compared results with gate up or down.
BTW, Welcome to FTE!
Last edited by superrangerman2002; Jan 3, 2006 at 12:57 PM.
He's actually burning more fuel and is completely clueless. Old myths die hard!!! 
