Any one know what kind of gas mileage a 4.0 2004 rubi should get? I am only getting maybe 10 around town if i am lucky. It is stock 29,000 miles on it with new plugs and air filter and runs great. It is a 5 speed manual trans.

Every driver gets different milage in what might be the same vehicle.
If I was driving your vehicle around town I would prolly only use 3 of the 5 gears.. I wouldn't keep it in any one gear till the rpm peaked. I also wouldn't LUG the vehicle in a gear. By doing this I betcha I would get closer to 14/15 mpg with the same vehicle.
One must remember one's right foot is where the mileage is.
Mileage don't necessarely come with the title.
You have five gears so you can find the correct one when driving at a constant speed that fits THAT gear. Using them all at every stoplight isn't needed.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

Agree with what Jim said. Is your check engine light on? What is your mileage on the highway?

Sean

I don't buy it...there's no way your going to get 50% better gas mileage by the way you drive.

Aside from the normal engine stuff, there is one critical item that will have a big impact on mileage --- tire pressure.

Under inflated tires act as a brake and will cause reduced mileage.

And, driving habits also have a big impact on mileage......

Well if the guy is hogg'n it in every gear and I drive like an old guy you might just go from 10 mpg to 14/15..
Now both crivers knowing what they are doing...you are correct. no way!
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

I had referenced this in another post about throttle body spacers, but how i drive my jeep has a big difference on my mileage...

"Just in changing the way I drive my 99XJ 4.0L 5 speed all stock I can make more significant changes to my fuel mileage. If I drive around aggressively and really rip through the gears I get about 19mpg, if I keep my foot out of it and drive around more normal, I average about 21 mpg, thatÆs a 14% increase in mileage with changing nothing except my driving. My peak HP and Torque for the engine didnÆt change at all either. Now if I avoid the highways and really keep my foot out of it, and shift very carefully and always keep it in as high of gear as possible; I average about 24mpg, which is a 12.5% increase in mileage over normal driving or a 25% increase over aggressive driving, and again no change in HP or Torque of the engine. Maybe I should start selling my right foot and a little common sense as a bolt on part to increase fuel mileage. I would have to find some advertising experts though."

Never thought I would quote myself. LOL

But this is partially why I asked what his highway mileage was. If he is sitting in a city, idling at stop lights all day long, or on a highway in stop and go traffic on the way to and from work, this all could adversely affect his mileage. If one uses their gas pedal as an on / off switch they will get much worse mileage than someone that keeps more constant or fluid pedal movements, and uses just the minimum needed for the gear application.

Sean

yea the way you drive is a big factor, idk about 50% but if you drive it nicely it will be nice to you, when i beat the ***** out of jeep and do brake torques in peoples driveways that i hate i get about 7-8mpg when i drive it nicely i get around 12.5 to 13, maybe try some synthetic fluids? or a bottle of fuel injector cleaner, though they shouldnt be that bad at 29,000 miles, unless you buy gas from a ***** station

I think something is wrong with the mileage you are getting.

I also have an 04 Rubicon with a 5 speed manual (4" susp lift, 1" body lift, HD bumpers & 33" tires).

I checked it two weeks ago in a combined of highway and city driving and I got 16 mpg.

You might want to use a GPS to check that your mileage is recording correctly. On a stock Rubicon the speedometer will show 3-4 mph difference than actual speed but don't know if the odometer is also wrong.

yea something is definitly wrong, i have 33's with 3.07 gears and the 4.0 and i get over 12, should go up now that i had my computer flashed