mythbusters did not take the tailgate off they simply put it down, with it down the air entering the back of the truck put down pressure on the tailgate decreasing mpgs. with the tailgate up it created a vortex in the back of the bed it would hit the tailgate go up back towards the cab and back into the bed. if you've ever seen anyone with a plastic bag in the back or something like that it'll get stuck in the vortex for awhile before blowing out.

 

 

In some states its illegal to drive without a tailgate of some sort.

 

I have two tailgates in the back of my truck. Does anyone think that will help?

 

didnt see that episode lol. i guess i had the vortex backwards too, oh well

 

Hmmm... I think if you have one up and one down that should cancel out everything and you should get an increase in MPG... So put one in the down position and weld the other one on top of the bed rails.. Make it like a big spoiler.

 

Good plan. I'll have the DIY up tonight.

 

Sawwweeeeeeetttttttt