JTPhoto JK

If you are running stock tires you probably won't see a gain until the cold weather comes. I saw most of the gains in cold weather, however, the programmer really takes advantage of premium all year round.

Greatdrs

I'm new here in this forum and everything i read is really nice.

JTPhoto JK

Pulled the Big utility trailer full of stuff to the dump on Saturday. Tow tune really helps climbing the hills by kicking the transmission down sooner as not to loose too much speed/rpm.. It also holds the gear longer before upshift.. I can see where a gear change with this tuner would make even towing a trailer enjoyable.

JTPhoto JK

OK its been 2 weeks with the Tow Tune and just over a month with the the programmer. Tow tune on 91 Octane is definitely my favorite. Mileage is a consistent 18-19mpg mixed. Throttle is very responsive now more so then when first programmed. This is one of the great things about this tuner, it has a self learning throttle control program within the programming. So far so good, the only thing we need now is a gear change. The programmer is not a replacement for proper gearing but it does make driving on 35s more fun..

hack99

Not bad mileage at all. My mpg seems to be tough to nail down, off roading it kicks the snot out my average. Normal driving (mixed city/highway) I'm guessing about 15-16 mpg here.

liveflatout

I have only had my jeep for a few weeks but I feel I can talk about fuel with some intelligence. There is a very big difference in fuels. I am not sure about all fuels out there but I run shell in everything I drive all the time and always get better milage. The reason for this is shell 91 has no ethanol. Although ethanol is great for using less crude it does have some disadvantages. The biggest of which for your ( or any vehicle) to create the same amount of power it needs to burn 30% more ethanol then non ethanol fuel. Now I am bad at math but using a fuel with 10% -20% ethanol your vehicle will have to burn more of that fuel to create the same power as non ethanol fuel. I have seen pumps with " may contain up to 20% ethanol on them. On my stock jk 4 door with me, the wife, dog and 2 kids loaded up got 13.2L/100km on the last tank of shell. That in included 2.5 hours of 1st gear wheeling on rocks and in mud ( did not think I would make it out). I then filled up again and so far am at 327.9 km and just over 1/2 tank. Now that is driving just mr and 80% 2 lane highway average speed somewhere around 95km or so.

jlau76

You're lucky that you have a station that can supply you with no ethanol gas. Not all Shell stations have 100% gas (i could be wrong), but getting to a Shell station for me is a PITA. But you're right, more ethanol = less fuel economy.

liveflatout

Oh I should also say that I have a manual trans. I was unaware that not all shells were no ethanol. And the 0% eyhanol is only on their 91. But I find ( in the Peterborough area) that even their 87 and 89 have less ethanol then the others. I out alot of km's on but most of it is between Peterborough, Bancroft and all places in between.

JTPhoto JK

Are you running with bigger tires? If not you need to get a programmer to maximize that 91 octane, 100% petroleum fuel that you speak of. 13.2L/100klm is not good for stock, you should be getting 11.5 to 12.5L/100klm. I easily get 13.2L or better with 35" tires, stock gears, and a programmer. Factory tuning is not designed to run 91 Octane so you are basically wasting your money. I have tracked my 08 Jeep JKU mileage for 3.5 years and premium only makes a slight difference in colder (below 0) weather..

jlau76

I really need that programmer. I am hovering high 15L/100km to low 16L/100km (my own calc, not the Jeeps) on 33 Mickey Thompson Baja. I might need to switch back to my stock rims/rubbers to see if there's an improvement, which I think their would be.