As I was driving to work today, I passed a pickup with its Tailgate down on the highway. This made me think, do a lot of people out there driver with their tailgate down in an attempt to improve mileage? This made me think back to the mythbusters episode where they tested the various ways to setup the bed of the truck for mileage. Tailgate up, Tailgate down, No Tailgate, a Tonneau Cover, and one of those "flow-thru" tailgate nets. Can anyone guess which got the best mileage?

 

mesh tailgate was the best
tailgate down is the worst
no tailgate, tannou cover and tailgate up are about the same....
http://www.youtube.com/watch?v=r3aqHbD-O9E

 

Haha, you did some research! I think its funny how may people you see with the tailgate down, thinking it helps their MPGs...

 

A person is also stupid who leaves their tailgate down while driving as the tailgate acts as a support for the box sides to keep them from flopping and wiggling from vibration.

 

That's news to me. I've always heard that trucks nowdays are engineered for aerodynamics to get the best fuel mileage with the tailgate up b/c that's how it belongs. Nice find.

 

oh yea well take your hood off and you get more air to your intake which help get better mpg.......

 

my mpg went down with the gate down...

 

There was an episode on Mythbusters on whether tail gate up or down was better. They proved that with the tailgate up it created a boundry layer and the air passed over the box. End result was about 5% better mileage than with the tailgate down or off.

 

They say with the tailgate up, the air swirls creating a high pressure area in the box, which keeps the air coming over the truck, from pushing down and creating downforce. With the tailgate down, the air comes over the cab, and pushes down on the back of the truck, causing downforce and more drag. My thought is this. If you built a truck that could be ran on a road course. You could put the tailgate down, and run a bar between the box sides to stabilize that. Wouldn't this downforce keep the backend planted in corners? Hmm...

 

That def doesn't work, keep the gate up.. It has been proven it doesn't help with the gate down..