I switched from regular to premium fuel and picked up 1.5-2 mpg on my 08. This was calculated by the avg eco on the dash but it made me happy. Im getting around 18 mpg on my 07 unlimited with 33's on regular fuel.

 

Op: quite a few variables going on for a 2,600 mile trip... Traffic, terrain, weather, etc. sounds to me like you are in the jk mpg 'ballpark'. I run an '11 2dr rubicon (4.10's) with 35" km2's on a 3" full traction, offload bumpers winch and all the goodies - I drive 84 miles round trip east day to work. My overall mpg is 15.4 hand calculated and 16.4 by the CPU. On the highway in 6th gear I get about 18mpg running at about 2300.

 

I have a 2012 JKU sport 6-speed with 35s and 3.21 gears. I am getting 16-17 on the highway and 18-20 around town, but I also don't use 6th gear anymore. I actually get better mpg in 5th because the motor doesn't work as hard. I am sure it will correct itself after a regear. Maybe if you manually shifted yourself down a gear your mpg's would go back up. Just a thought.

 

I have 2012 Rubicon 4.10 gears auto. I just put 35 on and used the procal to adjust for tires and get 18-19 if I drive 65mph.

 

I have also noticed my mileage drops a lot if I go over 65

 

And it will,the faster you travel,the faster your miliage will suck.I have a lot of mods and our JK is heavy we avg hwy 18-20,city 16-18.Its all about the skinny pedal

 

I can sympathize with robinson86. My '12 is a Rubi w/ hardtop, 4:10, 34s, TF Leveling Kit, and, last night, I just added the PSC Brawler Lite front bumper. I started out around 15mpg stock and am averaging about 13.5/13.9 around town now. Not complaining mind you. It's just the sad fact that our fantastically fun to drive vehicles are not good daily mpg drivers...

As an fyi, I use an app on my phone to keep track of maintenance, mileage, etc. and expect, it'll drop a bit more once I get the rear bumper on. However, summer is right around the corner so the hardtop will come off so I should get a little of that MPG back.

 

Whoa! I haven't even thought of using this. Should I since I jumped up to 34s? If so, what's the best place to pick up one of these ProCal doo-hickey, thing-a-ma-giggers?

 

Driving styles def affect mileage big time. I find if I just set the cruise control at 60 I get the best efficiency. The economy really drops off going any faster mainly due to aerodynamics, or lack there of. Lol

Btw I'm getting 23 mpg on the computer if I reset it doing 60. With my mix of driving city and highway I'm averaging 18 on my 2012 jku auto.

 

I have a rubi with 35's and 3.5" lift
Just did 1200 miles last week
Got 19 highway and 16 combo running around Dallas

I found a problem on mine and modified it

The insulation blanket on the underside of the hood was blocking
The air inlet of the Air filter
I used some scissors and trimmed
The insulation from that area

Previous to trimming the best I got
Highway was 15-16

Here's a couple pics

This shows how stock the insulation
Almost covers the inlet and the hood
Is not even fully shut yet



This pic shows how I trimmed the corner off the insulation



This pic shows the increased area for air flow
Actually I'm going to trim it back a little further now that I've proven
The increased mileage



BTW the sport models do not even have the insulation, so by removing a small corner should not cause any
Problems and should still quiet the engine noises



Sent from my iPhone