Some recent threads are reporting worse mpg's with a cai.

Right now, your dash mpg numbers are meaningless, as the computer still thinks you are on stock tires. So, your speedo/odo/mpg's/etc are all innacurate...

A programmer will let you tell the computer that you have bigger tires, which will make your speedo and odo accurate again. (and the shift points for auto's). As far as the dash mpg goes, it will still be just as inaccurate as always. Much better to pen & paper it...

A 'tuner' will do everything a programmer will do, but will also let you tune for performance and mpg's. This is the better option if you can afford it.

 

I think the thought that CAI's increase mpg's is the biggest internet myth ever.

 

I fixed the wallowed out hole on my trackbar and my gas mileage went back up to 17 mpg. I added the rockjock weld on bracket which works pretty good. Couldn't believe my gas mileage went up. I was barely getting 15 mpg with the trackbar messed up. How often are you guys checking the trackbars?

 

Stock JKU, Rubi Tires, Auto, 3.73 gears, hard top ~16mpg (computer), but it's been cold here. During the spring and fall usually around 17-18mpg with mix of H/W and City driving (87 octane).

 

If you really want to know your MPG keep it constant, don't reset your odo every time you fill up.

I haven't reset mine in a year. 2010 Rubicon, every thing stock except K&N.
14.8 mpg 2010 average. 8700 mi.

I do 90% city driving when I'm not offroading.
Tom

 

how is it possible that im only getting 9-11 mpg on a stock 08 unlimited rubicon with 315 / 75/ 16 duratracs when everyone else is getting extremely better mileage unless they run 40" tires?

 

32's with 3.21 gears, 6 speed, Volant CAI and MBRP Exhaust.

15-18 City depending on how i drive.
18-19 Highway (65-70 mph in 6th)
20-23 County Highways (40-55 mph in 5th gear)

EDIT: This is NOT computer, this is calculated off fillups

 

My stock Sahara, auto, w 33" gets 20 - 21 when I drive on cruise control, (hwy 65mph) tires inflated at full 32psi.

jp

 

Since I did all my mods, I still haven't used a full tank, so I will update come Monday when I am guessing I will have gone through my first tank.

 

ive got an 07 on 35s with 4.10s and im getting between 16 and 17 mpg