Pickup Truck Aerodynamics

[SmaartAasSaabr]

Here's a question for you guys. On a typical fullsize pickup, would I have better fuel economy with the tailgate up or down?

/edit/ My observations with leaving small crap back there (leaves, small pieces of trash that assholes just throw in the box when you're parked on the street ) seems to point that there is more or less no turbulence inside the box with the gate up. With the gate down everything just flies out the back as you would expect.

[V1 Dave]

Google search found an engineer (Car Talk) that says leave it up!
http://www.google.com/search?hl=en&i...=Google+Search

[AirMoore]

2 words:
Drag Coefficient: One reason why motorcycles have extreme high speed issues.

[SmaartAasSaabr]

2 words:
Drag Coefficient: One reason why motorcycles have extreme high speed issues.

Come on think of my truck, if you touched 85 you could kill yourself

[SmaartAasSaabr]

Google search found an engineer (Car Talk) that says leave it up!
http://www.google.com/search?hl=en&i...=Google+Search

Ah... but there's gotta be a critical velocity where the tailgate up is better than down then. Then again aerodynamics aren't much of an issue below say 45 miles per hour.

[SmaartAasSaabr]

Here's another idea.

Next Saturday I'm hooking up my carhauler and going to grab another Saab 900 Turbo(#9). Now what if I made a big piece of plywood to replace the tailgate, that would be angled from the tailgate to the bumper of the Saab.

[HighVoltage]

I seem to recall Mythbusters doing a segment on this as well. They also found improved mileage with the gate up vs down.

[eviltwin67]

I saw that Mythbusters too and up is the way to go. It has sonething to do w/the air pocket that is created in the bed w/the tailgate up.

[ZO6Vette]

None. You would do better with it off!

[Sparkknocker]

Invest in a tonneau cover. Extang makes a nice soft tonneau cover. www.truckcandy.com

You will save money on gas and it helps with drag