I've been averaging 350 per tank with an equal mix of highway/city.

Must just be me, I have completely stock truck in tune and dont get anywhere near 350 a tank.

 

350 on a tank isn't outrageous. I was getting 16 MPG when my truck was stock. My SD rack, 3" lift, steel bumpers, sliders, skids, and the 255 85 MT tires took care of that though.

Now I generally get more like 11 MPG in mixed driving after adjusting for the bigger tires. (My wife has a much lighter foot, and has managed to get it up to 13.5 MPG on the highway.)

 

 

So, is it just mine (or all 04's) that remain in Sport mode even after having parked her and powered off and startup? It seems that everyone else needs to engage it after every startup.

 

I have a ARB bumper, 265/50/20 tires and am about to do a 2" lift. I average 11.7 mpg now. I hit sport mode when I want a little more pick up. I will also try using it around town. After reading this thread it makes sense to us it for in town driving. Im a pretty aggressive driver so I have myself to blame for poor gas mileage.

 

I'm semi-aggressive and I get around 330-350 miles to a tank. But I'm sure my 2" OME lift and roof rack, once I get it, will soon end that.

 

Antmen mine is also stays on once I engage it even after I turn the truck of and on again. I have to hit the S button for it to go off.

 

Mine does that too.

 

Call me crazy, but I think I have a Discovery that likes the Shell Premium gasoline.
The truck sips it like a fine wine and gets a very impressive 16-17 miles/gallon.
IT SHOULD WIN SOME KIND OF GREEN ENVIRONMENT AWARD IF YOU ASK ME!!!
If I try a different brand or a lower octane the truck does not get nearly the gas mileage.
(320-350/tank with Shell Premium, under 300 with others)
It is not worth it, in my case, to try to save 10 cents a gallon at the gas station across the street because I seem to loose mileage.
I have only used the Sport Mode a couple times... may have to try it around town.

 

My 2002 stays on as well.