Rich wrote:
> I drive with the tailgate down when I use the pickup unloaded.  It does save 
> fuel because up, it can scoop up enough air pressure at 50 mph to cause 
> significant drag.   I have seen some kind of rubber or polymer sheet on some 
> pickups with big holes in the sheet stretched across the back, and no 
> tailgate.  I assume it is intended to reduce drag but at higher speeds it 
> seems that perhaps some significant drag may develop to obviate the purpose.

This is exactly what MythBusters disproved.

Having the tailgate up creates a vortex behind the cab to the rear of 
the vehicle and actually creates LESS drag when the air flowing over it 
of the main airstream interacts with the vortex instead of dragging 
along the bed of the vehicle.  A "buffer zone" of circular air motion, 
so to speak.

The various "remove the tailgate" or "leave it down" products are snake 
oil. Those netting-across-the-back products were proven in the show (as 
was leaving the tailgate down) to have LOWER gas mileage than leaving it up.

Do your own tests (as they recommended) scientifically if you don't 
believe them, but they did a pretty good job of making the tests fair, 
and tailgate up won all categories.

Nate
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