My friend's dad says driving with your tailgate up on a pickup truck..... Is this true?

Question

is better than driving with it down.....
Gas mileage is better with it up, noty down
true or false?

Answer 1

yea that pretty much depends on who you talk to, everyone will have their own theory, and every truck has different aerodynamics and will react differently.

the argument for the tailgate being down would be that the air flows right out the back when it would otherwise be basically hitting a 'brick wall' thus slowing you down.

the argument for the tailgate being up would be that a pocket of air forms in the bed of the truck while you are driving, and the air will just glide smoothly over it. try putting some dry leaves in the back of your truck and go on the highway and see if they are still there when you are done. they should be, since most trucks are designed this way.

you are better off just figuring it out for yourself by simply filling your tank and driving til its empty with the tailgate up, record the mileage, and then do the same with the tailgate down and see which way gets you farther.

or if your too lazy to do that id personally suggest keeping it up.

Answer 2

There is alot of opinion in this question, and no real fact - aside from what Mythbusters tested.

Most people look at a pickup, and imagine the airflow coming over the cab and terminating at the back of the bed like it's hitting a wall. If that's the case, then it would probably have a pretty major impact if you drive at more than 25mph!

But, it is a huge assumption that the airflow over the top is coming back down into the bed. As the Mythbusters test showed, people that spend time with car designs, tuning them in wind tunnels, the air coming over the cab may well land just behind the tailgate! And that it's the act of lowering the tailgate that is actually interrupting the airflow and creating drag!

If the pickup is a new model, within the last few years, I would expect that it's body shape has been tuned and that you would obtain your best performance results with the tailgate up. And older model would could easily benefit from it being down. You could simply test as has been suggested, but if you do, keep in mind to be careful with your methodology as tire pressure, ambient temperature, wind speed and direction... and many other things, will also have a bearing (Mythbusters accounted for this by doing the test in two different pickups at the same time on the same route, though I would have like to have seen them repeat the test on the return journey with the gate down on the one that was previously up and vice versa to confirm it wasn't due to some minor unexpected difference in the "identical" pickups).

Answer 3

On a recent Mythbusters episode on discovery channel they tested: tailgate up, tailgate down, cargo net gate, and a flat bedtopper. The result was this. The tailgate up actually got worst mileage, followed closely by topper, then the gate down, and the best milage was acheived with the cargo net tailgate. They surmised it had to due with the weight of the tailgate/topper and wind resistance combined.... Sorry friend's dad!

Answer 4

With the tailgate up, the resultant air flow actually produces less drag on the pickup than with it down. Strange I know, but true.

Answer 5

It makes little or no difference. Apparently you didn't catch that episode of Mythbusters.

However, adding a cover to the bed, like a cap, or a tonneau cover can yield an improvement in gas mileage.

Answer 6

According to stringent testing....it makes little or no difference!...Though Mythbusters showed better mileage with it up...

If your dad drives a pick-up for anything other than hauling junk by choice, however, the facts are hardly likely to sway his opinions!

Answer 7

False...tailgate up creats air drag and decreases gas milage. That is why drivers that must have a tailgate to keep things in use an "air flow' tailgate. One that air can pass through.

Answer 8

True... it cuts wind resitance but it dont help that much but if u drive allot it adds up

Answer 9

Mythbusters tested this one out.... Up is better according to their testing.

Answer 10

TRUE,remember,most older people are pretty smart.