Open windows (04 Dakota pickup - air flows IN through rear window - extra drag?)

[Specaled]

In my Baby Truck I usually drive with the driver's window and back sliding window open because I have no AC and I hate the heat. I notice that the wind doesn't flow into the truck through the drivers window but from the back window. I'm just wondering what kind of drag this causes if any. Any ideas?

[California98Civic]

Originally Posted by Specaled

In my Baby Truck I usually drive with the driver's window and back sliding window open because I have no AC and I hate the heat. I notice that the wind doesn't flow into the truck through the drivers window but from the back window. I'm just wondering what kind of drag this causes if any. Any ideas?

If air is coming in through the back window it must be exiting somewhere, and that must be the driver's window. I would imagine that all can't be good for aero.

[Specaled]

Yes that is what I would assume it's doing, but is that better than coming in the driver's window and slamming the inside off the truck then going out?

[SecondWind]

As always, pick a day with moderate temps (or late at night), and run a mileage test with and without the windows open. Then you can answer the question for all of us!

[aerohead]

Originally Posted by Specaled

In my Baby Truck I usually drive with the driver's window and back sliding window open because I have no AC and I hate the heat. I notice that the wind doesn't flow into the truck through the drivers window but from the back window. I'm just wondering what kind of drag this causes if any. Any ideas?

The static pressure outside the truck is lowest near the wind shield header and A-pillars.Higher pressure in the bed flows in to attempt reaching equilibrium and exits through the window.
I just did 1,379 miles like this and the mpg was good enough that I don't think it's an issue.I suspect that the drag is offset by not operating the AC compressor.

[Specaled]

Thank you Aerohead. I can feel a little bitbetter driving now =D. The clutch on my AC was out when I bought the truck and I don't feel like paying 300 bucks for a new one.

[aerohead]

Originally Posted by Specaled

Thank you Aerohead. I can feel a little bitbetter driving now =D. The clutch on my AC was out when I bought the truck and I don't feel like paying 300 bucks for a new one.

I've got a working clutch,but the blower hasn't worked since last September.And I'm gonna need a fan(with the heater core) for auxiliary engine cooling if the grille block can't provide enough air to the radiator.