Turns out I was somewhat mistaken... the difference DOES weigh in favor of windows down and AC off until the speeds become much higher (~80+?) and the drag of the windows being down surpasses the HP loss of the engine to the compressor.

My last highway trip was 318.3 miles using 13.244 gallons of gas doing 60 mph with the windows down and resulted in 24 MPG.

Luis[/b]

You must have a magical Jeep, or you drive down hill all the time.
If you are getting 24mpg, please let us know I would love to get that kind of milage.

This is info directly from Chryslers press release.
EPA Fuel Economy (mpg City/Hwy) 19 mpg/23 mpg and that is for the
2.4 litre engine.

For the 3.7 it gets worse.
EPA Fuel Economy (mpg City/Hwy)
Automatic 16 mpg/20 mpg
Manual 16 mpg/21 mpg

Or you can read the specs at:
http://wwwsg.daimlerchrysler.com/SD7DEV ... 96,00.html?

Nothing magical about it. I've gotten as low as 17.25 mpg on a tank where I hauled the boat to the ramp and back, and then had a touch of leadfoot for a small part of the rest of the tank. That 24 mpg trip was MOSTLY highway driving with the Liberty TOTALLY stock and the tires @ 35 psi, using the cruise at 60 mph with most of the mileage on the interstate totally uninterrupted. I'm pretty sure that the sticker on my '05 said 17/21 mpg not 16/20.

Don't forget that for them to post 21 as the highway rating, that it has to get much better than that during optimal cruising. I still remain convinced that running with the windows down and the air turned off helps substantially.... maybe the sunroof being open helps reduce the drag from the windows? I don't know. But I fill up very carefully every time making sure that I fill the tank all the way, so I'm sure that the gas mileage is correct.... unless my odometer is working incorrectly. Oh yeah... I typically take off more like a tortoise, than a jackrabbit... that REALLY helps.

Try this for your next tank....
1) Make sure your tires are FULLY inflated to 35psi or better
2) Run with the windows down and the AC off (no fan either... some of the settings engage the AC even when you don't have the button pushed in) as often as you can stand
3) Accelerate VERY slowly (pretend there's a raw egg between your foot and the accelerator)
4) Don't exceed 60 mph
5) Maintain a steady speed as much as possible (this means if traffic is running ~60 mph only go 55 so you never have to stop or slow down, and USE THE CRUISE CONTROL)
6) Avoid driving in the middle of the day if you can since the air is much hotter and has less oxygen in it (it actually makes your engine perform more poorly).

Force yourself to adopt these habits as often as you can stand, and if you don't already do this stuff, I virtually guarantee your mileage will increase a couple mpg (maybe more) on average. Of course, if you're lifted 6" and are running 35" tires, there's no help for you... LOL Even a 2" lift and 31" tires pretty much guarantees you aren't likely to exceed ~21 mpg tops.

BTW, my AVERAGE tank of gas gets me between 18.5 and 19.5 mpg.

Luis

4) Don't exceed 60 mph

Actually, I find that if I do about 70 mph, I get better mileage than if I do 60-65 mph.

You only THINK you get better mileage at 70. If you use the cruise, and keep your other driving habits consistant you WILL get better mileage at 60 than at 70. I absolutely guarantee it.