Serious H2 SUT gas mileage tip

[GamblerHummer]

I just got back from a long trip . I got 15-16 mpg by driving 65. Anything in the 70 range and above I would drop back down to 14.2. Then I discovered a tip that if you have a SUT you have to try. Keep all your windows up along with moonroof, with the execption of the rear window leading to the truck bed. When do this and keep that rear window down I gained mpg by doing this . I can get 17-18 mpg on the highway now running 65 and no air. I am also getting a consistent 13.3 mpg now and sometimes as high as 14 depending on stop and go around town doing this. I am not sure why leaving only the rear window down is having the affect, and I know it sounds crazy, but please give it a try.

[GamblerHummer]

I just got back from a long trip . I got 15-16 mpg by driving 65. Anything in the 70 range and above I would drop back down to 14.2. Then I discovered a tip that if you have a SUT you have to try. Keep all your windows up along with moonroof, with the execption of the rear window leading to the truck bed. When do this and keep that rear window down I gained mpg by doing this . I can get 17-18 mpg on the highway now running 65 and no air. I am also getting a consistent 13.3 mpg now and sometimes as high as 14 depending on stop and go around town doing this. I am not sure why leaving only the rear window down is having the affect, and I know it sounds crazy, but please give it a try.

[VTSTOMPER]

I love to drive with that window down...the wind is just right, and it is very calm with it all the way down. I have never looked at it like you did, I will have to. They say all the windows up though gets you less drag, and that gives you more MPG!

[dochummer]

If you're not using the AC then you should get better gas mileage whether you're in an SUT or SUV... Did you try the expirement with the back window up and with the AC off? I've seen a lot of people drive with the tailgate down on the highways, apparently supposed to improve gas mileage also...

[Dan]

That rear window is great! The overhang lets you open it a bit even when it's raining. If you open the back window a couple inches and tilt the sunroof you get great circulation with hardly any noise.

[dochummer]

Sorry Dan, I was going to reply to that last message of yours...but that avatar popped up full size again.... doh!!!

[H2_SUT_SC]

15MPG?!?! GBUS, I'm lucky to get 10! Filled it up twice so far, I'm hoping it'll get a tad better. Maybe once I throw on the supercharger.

[Dan]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by dochummer:
Sorry Dan, I was going to reply to that last message of yours...but that avatar popped up full size again.... doh!!! </div></BLOCKQUOTE>

This should keep you busy for a while

[ParchedMosquito]

I would think it is caused by the reduction of turbulence.

When airflows over a square cross section (with a short depth) turbulence is high. In the case of the SUT with the window down, a pressure differential is created between the interior and exterior of the car. The solid boundary is removed and the air does not "fall over" the edge reducing the turbulence.

*takes off engineering hat*

My first post.

[HummerNewbie]

Welcome Parched.