2005 Rubicon Gas Mileage

hi campbell, i also have an '05 rubicon

and i too am a little concerned about mileage.

lol....yes it does.

you definately have cause for concern. my rubicon is an automatic and im still getting better mileage than you. after several tanks (ive only got

700 miles on it) im getting about 12 mpg. i previously owned two '03 rubicons (both with automatics) and they both got 14 mpg.

lol dont pay that sticker any mind. ive never got the rated mileage on any jeep ive ever owned. they either pick those numbers out of a hat or theyre running in a vacuum chamber with no wind resistance. :-)

something is definately wrong. im also a little concerned about my '05 and im getting 12. im hoping its just a break-in type issue but i dont remember either of my '03 auto rubis ever getting below 14.

Is anyone using larger than stock tires? That will cause an odometer (and speedometer) error that will appear to affect your mpg.

It has the standard LT 245/75R-16E Goodyear 31" MT/R's mounted on the 16 x 8 Jeep "MOAB" Wheels. And GPS speed matches the speedodometer.

It really is getting ~8.5 - 10 mpg in the city, using the "crude" fill-up gas pump/mileage method.

I have a 2003 Wrangler Rubicon with the 5 spd, 33x12.50 tires, and ~10,000 miles on it. I drove it to Moab from Colorado Springs in March and I checked the mileage on two tanks of gas. They were both a combination of two lane highways, and Interstate 70 driving. The first tank I checked I got 17.6 mpg, and 17.8 on the second. I was holding it to 65 mph on the interstate.

I don't have a problem with the gas mileage as much as the lack of power. My

1991 Wrangler with 4.0L/5sp had a lot more power than my Rubicon! I wonder if anyone has tried a non Rubicon ecm in a Rubicon? And would it be as easy as unplugging the stock one and plugging in a non Rubicon one or do they interface differently?

Jeff Hendron 2003 Jeep Wrangler Rubicon MatrixOne Support Skyjacker 4" lift, JKS Disconnects Agilent Technologies Fabtech Front Bumper, Rock Krusher Rear Bumper Co Springs, Colorado Rock Krusher Rock Rails, Custom Swingout Tire Carrier (719) 531-4319 33x12.50 Goodyear MTR's, Mickey Thompson Classic Lock Wheels jeff snipped-for-privacy@agilent.com Bush Whacker Fender Flares, Warn XD9000i Winch

Yamaha WR250ZF

Campbell C Freeman wrote: : Hello,

: I have a 2005 Rubicon, which I purchased about 2.5 months ago and it : currently has 1,800 miles. I noticed shortly after driving it for a few : days, that the gas gauge seemed to move to the left rather quickly. I also : seemed to be putting gas in it much more often that my 2001 TJ, which I used : as a trade. I did the "fill-er-up, same place, same pump, same delivery : rate, & cut-off at the pump routine" for a week or two and was amazed to see : an average of 10 mpg. The Rubicon (with California Emissions), has an EPA : Rating of 15/19, whereas my 2001 TJ had a rating of 16/19. I averaged about : 16 mpg with my 2001. Most of my driving is city.

: I did a VIN recall inquiry search on the

site and found there : was an outstanding Emissions Recall - Reprogram PCM: Notification Code D46, : for this vehicle. The incorrect version of software was initially & : originally programmed into the Powertrain Control Module (PCM), which "could : cause the On-Board Diagnostic (OBD) fuel system monitor to malfunction." I : called my dealer that day and scheduled an appointment to have the computer : reprogrammed. Interestingly enough, that same day I received the exact same : recall notice from DaimlerChrysler in the US Mail.

: I took the Rubicon in the next day...reprogramming took about an hour, and : off I went. I took a trip out-of-town over the weekend, did some highway : driving, and averaged about 17 mpg on 2 tanks of fuel. Three days later I : was driving along in town when the Engine Light came on, began flashing, and : the motor was running on 5/6 cylinders; skipping horribly. I pulled in to : where I was going and called D/C 24 Hour Roadside Assistance. A tow truck : was there in under 20 minutes, and off 'she' went to the dealer. Next day : I was there when they opened, and stayed to find out what was the matter. : The technician told me the computer code said "running lean." He found gas : all over the # 6 spark plug and it was fouled. He replaced it but it still : ran rough. Next he replaced the injector for that cylinder and that took : care of the problem. Off I go, and 'she' is running just fine, but I am : still getting 9-10 mpg in the city. This is the 4.0 L I6 w/ a 6 speed : manual (the 'new' German transmission), and a 4.11 gear ratio. It is a : "stock" Rubicon with everything but the hardtop. To me it runs fine with : the exception of this gross gas mileage. Something has to be wrong.

: Even though I do 95% of my driving in the city, I seldom get above 2 grand : in either 4th or 5th gear. I am not a "lead-foot." In fact, I "baby the : thing" since it is so new. You are in 4th gear at 40 mph with this : transmission and rear end. So I usually don't go over 40 in the city, only : occasionally getting to 5th on some longer stretches and of course, 6th on : the highway.

: What could be causing such terrible gas mileage? I understand that new : motors use a little more fuel during break-in, but this is half of the : rating (which I realize is not real-world). I am not running the AC at this : point in the year yet either.

: Any explanations, suggestions, and/or "fixes" would be greatly appreciated. : I will also call the dealership and report the extremely poor mileage.

: Thanks very much,

: Campbell Freeman : South Carolina

Your Rubicon has 33" tires and 4.10 gearing, not a great ratio for that size tire. Regearing to 4.56 would restore the power caused by that

4.10/33" combination.

Jerry

Jeff Hendr> I have a 2003 Wrangler Rubicon with the 5 spd, 33x12.50 tires, and ~10,000

I have an '05 Sport, with the 6-speed and 3.07 gear ratio. At first I was getting around 15mpg (some tanks reporting as low as 13mpg and occasionally as high as 16mpg), Now, with 4K miles, I get 17-19mpg. I don't remember what the EPA rating on my model is. I do tend to accelerate quickly, but I keep the engine speed low (less than 3000 rpms) and try to stay light on the pedal on the highway.

The only thing I can suggest is maybe the lower gearing and the extra weight of the Rubicon combined with the break-in is giving you such bad mileage. However, 10mpg does sound really bad. My dad's old '83 Ford Clubwagon (351 V8) performed almost that well near the end of its life.

Your speedometer (and gas mileage figure) is invalid unless you re-calibrated it to compensate for the 33's.

My speedometer has been recalibrated and is consistent with what my gps receiver displays.

Jeff Hendron 2003 Jeep Wrangler Rubicon MatrixOne Support Skyjacker 4" lift, JKS Disconnects Agilent Technologies Fabtech Front Bumper, Rock Krusher Rear Bumper Co Springs, Colorado Rock Krusher Rock Rails, Custom Swingout Tire Carrier (719) 531-4319 33x12.50 Goodyear MTR's, Mickey Thompson Classic Lock Wheels jeff snipped-for-privacy@agilent.com Bush Whacker Fender Flares, Warn XD9000i Winch

Yamaha WR250ZF JimG wrote: : Your speedometer (and gas mileage figure) is invalid unless you : re-calibrated it to compensate for the 33's.

: -- : JimG : 80' CJ-7 258 CID, HEI : 4.56 Gears, Lock-Right F&R : 35" BFG MT on 15x10 Centerlines : D44 Rear, D30 Front. SOA : Dana 300 w/4:1 & Currie twin sticks : Warn X8000i w/ dual batteries

: 00' TJ Sport 4.0L, 5sp : 4.56 Gears, TrueTrac rear : 33" BFG AT on 15x8 Eagle Alloys : D35 Rear, D30 Front. 3" Suspension Lift

:> I don't have a problem with the gas mileage as much as the lack of power. :> My :> 1991 Wrangler with 4.0L/5sp had a lot more power than my Rubicon! I :> wonder if :> anyone has tried a non Rubicon ecm in a Rubicon? And would it be as easy :> as :> unplugging the stock one and plugging in a non Rubicon one or do they :> interface :> differently? :>

:>

:> Jeff Hendron 2003 Jeep Wrangler Rubicon :> MatrixOne Support Skyjacker 4" lift, JKS Disconnects :> Agilent Technologies Fabtech Front Bumper, Rock Krusher Rear Bumper :> Co Springs, Colorado Rock Krusher Rock Rails, Custom Swingout Tire :> Carrier :> (719) 531-4319 33x12.50 Goodyear MTR's, Mickey Thompson :> Classic Lock Wheels :> jeff snipped-for-privacy@agilent.com Bush Whacker Fender Flares, Warn XD9000i Winch

Thanks for the clarification.

JimG

mic,

I believe you are right. I filled up today. 100 miles since last fill-up and it came out to ~11.75 mpg. That is up ~ 3 mpg in 4 days of driving. All city driving.

Thanks for the info 'mic canic'.

Campbell C Freeman

Mr. Freeman, I was wondering if you ever solved your mileage problem? I just bought an Unlimited Rubicon with the Sahara package last week and am experiencing the same 10 - 10.5 mpg that you were experiencing. Mine is currently at 800 miles with several tanks of gas. Thank you for any info you may have.

Gerald