I am having the same problem!!!!! I drive 25km to work on a country road that I can drive like the hwy. when I first got my JK I got 500km to a tank and now get 380km. I live at 2500 ft above sea level, have a few hills going to work but nothing much. The dealership says they can't find anything wrong, so now I have to do a milage log. After 3 tanks of fuel they will send a report to Chrysler to see if they think everything is ok. I was using it as a daily driver but have bought a car to get me back and forth to work. This is crazy I loved my JK but my other half drives a full size dodge and gets better gas milage.

 

Summer time fuel Blend

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