Do you really get better gas mileage when you leave the tailgate of a pickup truck down?

Answer 1

One would think so, but Mythbusters did a test on that and discovered that contrary to common perception, you'll actually get better mileage with the tailgate up than down.

Has something to do with a "ball" of air that gets trapped in the bed and actually reduces drag when the tailgate is up. When the tailgate was down that ball did not form and fuel economy dropped about 5%.

Answer 2

I have seen several studies on this and the data and science does not support it. The way a pickup is designed, with the draft coming over the top of the cab, allows the air to flow over the cab and over the tailgate with little or minimal drag.
When you put the taigate down it creates a pocket behind the cab that actually adds drag, therefore causing the truck to get less gas mileage than when it is up.

Answer 3

Leaving the tailgate down worsens gas mileage slightly.

The reason is as follows:

Drag on the car has to do not only with air "running into" objects, but also with the fact that a low pressure "wake" can form behind the object. This low pressure wake behind the cab of the truck increases the drag force on the truck since the surrounding air is at higher pressure (the pressure differential opposes the motion of the truck). When you leave the tailgate down, it lets air freely travel through that area and increases the size of the low pressure wake, thus increasing drag.

Answer 4

No you do not get better gas millage with the tailgate down..In fact if you have anything in the bed of the truck you can get a ticket for having it down.As well as My grandfather who was a truck Driver and mechanic for 50 years always stressed that leaving the tailgate down was not stuctural sound because of the gap in the box. Over time it would cause the box to become unstable on the frame. Just a theory of coarse. But one I haven't found fault with.

Answer 5

I read where Lockheed Martin once did a study on this using their wind tunnels and found out that you actually get better gas mileage with the tailgate in the closed position. And like that other person said I have heard that in some areas you can get a ticket for having it down. I put one of those roll top bed covers on my pickup and they claimed that it would improve the gas mileage but it didn't.

Answer 6

actually, leaving the tailgate down will increase drag.
As air travels over the cab, it will directly hit the bed causing extra downforce/weight. With the tail gate closed, there will be a "air bubble" trapped inside the bed, hence causing the air to go over the cab and over the bed.
Watch "Mythbusters" on the Discovery Channel

Answer 7

2004 Dodge Ram...Tailgate up=16.5mph...Tailgate down=16.0mph...Tonnau cover=17mph
These are averages over many miles on my personal truck.

Answer 8

No, It's a myth. Speed of your truck has more to do with mileage you'll get (55-65 MPH).

Answer 9

yes you do,,i own a repair shop,,and use a truck as a go getter,,and we leave the tail gate down on it all the time,,it actually gets better mileage,,because there is less resistance on it,,from the wind,,when i go on long trips i leave it down also,,but believe me it help,s,,good luck ,,i hope this help,s.

Answer 10

No. They genuinely suck gasoline like it became $0.50 a gallon. besides Land Rover vehicles has the backside reliabilty score of any variety offered interior the U.S. -- and you will spend a ton of time and funds on maintenance -- and coverage is super-high priced. don't comprehend why human beings purchase Land Rovers and variety Rovers -- anticipate they think of that's a luxury variety that makes them look solid. each time I see somebody utilising one, i'm thinking how ineffective and dumb they're.