I have an 05 quad 4x4 with the H.O. and 3.92 gears and I'm getting 15 - 17.5mpg with mixed city/hwy driving.

It's normally better if I use the 93 octane but then I start hammering on it and that goes out the window!

I was pleasantly surprised at the difference the better gas makes in the H.O. and my foot likes it too.

The LSD is also nice when taking off and keeps the tire spin under control... It would spin instead of launch without it!

The H.O. with the 3.92s should get worse mileage but I have a lot of hill terrain here in Upstate NY and I think it balances out.

The lower gears keep the tranny from fishing on inclines and steep hills. That seems to help if I keep my foot from getting heavy.

My father in law has a 05 club 2wd with the 6 in it and 3.55s and he said he gets 19 - 20mpg.

He's not a heavy foot though and his truck weighs less too.

 

I have a 06 TRX 4x4 4.7 H.O and I get 14.6 - 15.6 around town and recently worked up in the Ga. mountains so I got to drive up there from Atlanta and I got to test out the H.O on highway. I got 18.5 - 20.3 @ an average of 70- 75 mph. And I must say when hitting the pedal @ 70 it just takes off and gets up to 100 quite fast. A note about the mileage computer...its more accurate if you reset it on startup or during your drive each day. After my work up in the mountains I returned to city driving without reseting computer and for 3 days it was getting 16.7 - 17.8 around town...which I knew was not accurate. So I reset it and after a few miles it went back to the 14-15 around town. I even drove up on one day to mountains and didn't reset computer and it was stuck ar 14.5 give or take .5 both ways. I was also getting about the same gas mileage with 87 and 93 gas. But like paying for 87 much better even with the power loss.

 

Uhm ya, it's not a current average. lol.. it's the total accumulated average mileage.

That is the nice thing about my mom's 01 Durango, it also displays current mpg.

 

So far, with 550 miles on the vehicle, averaging 16.0 mpg; i.e. commuting to and from work. QC with 3.55 rear end.