I haven't updated my full chart yet, but I am almost done putting the data into excel. I now have over 20k miles and have records of every single full up. Between February and December I have an average of about 16.6 mpg. Some numbers are above 19-20 due to highway and some are around 11-12 due to towing. I'll try to complete the data analysis and post the results by tomorrow evening. Again, this is for the 2012 JKU with 3.73 rear and manual trans. The rubi with 4.10 will be a little worse and the mall crawler with 3.21 will be a little higher.

 

I'm on my fourth fill up of my '13 JKUR. When I drove it off the lot the digital read out was in the 17.6- 17.9 range for the week. I noticed it drop to around 15ish after the next fill up. Then hover around 14.6. I'm still on stock wheels and no lift yet (installing this week hopefully). I'm wondering if the initial fill up came from where it was manufactured? Maybe a different blend of fuel then what's here in Jersey this time of year. I calculated by hand and confirmed 14.6. Oh well, this should be interesting to watch when I get my 37's thrown on I will be keeping my 4.10's for quite a while.

 

I used to look at this all the time, but after 3 Jks and settling down to one, here's the bottom line...

2007 2 Door = 18 MPG in CO (stick and 3.21s)
2008 4 Door = 19 MPGs in CO (stick with 3.21s) added 35s tires and only went to 17 MPGs
2010 4 Door Rubi = 18 MPGs in CA (stick with 4.10s)
2012 4 Door Rubi = 16-17 MPGs in CA (auto with 4.10s)

It's a brick, going downhill is great on the highway and climbing is bad :( Stop and go kills any hope of fuel efficiency... I look at it this way, how much do you really save between 16 MPGs vs 25. MPGs? I think the penstar was just more power but same MPGs.

My best advice... Pay your JK off and buy a Kia Soul for commutes or driving in the dark with no one watching

 

I find it hard to believe it was noticeable on performance feel. Yes it supposedly does this but nothing I've ever felt as noticeable.... In trucks or jeeps.

 

I also have a '13 (2 weeks old and 1050 miles) and I'm seeing my MPG around 15-17 on screen. I have an unmodified JKUR.. But, I'm hoping to see a small bump above where we are now

 

I am sure you will. I have a huge Gobi roof rack and am getting that in my '10.

 

I have a 13 and went from 18 to about 16-17. I think the winter has something to do with it.......and your foot can always cause a decrease in gas mileage to get the big block moving

 

Frankly, I'd rather spend the money on the fuel, it would take a lot of driving to justify paying for another car with better mileage, but more importantly, I wouldn't be caught dead in a Kia Soul, let alone in the dark.

 

No it will drop even more! Haha jkjk i wish i was at 16! Im at 14 stock!!!
I have a 4 door with 4:10 gears

 

I have a 2013 JKUR Manual with just over 1500 miles and I got about 15mpg on my first fillup, I've slowly edged up to 16-17. Towing an 88 YJ for 50 miles dropped me down to 13mpg on the last fillup

It is winter so I expect a slight drop in mpg. Come summertime I am expecting much better.

My 05 TJ average 13-15 in winter and 15-16 during summer, all after lift and tires.