Im looking to improve my gas milage on my 6.4 hemi jk at least on the highway because that thing gulps fuel like there is no tomorrow. Some guys suggested using a tuner like Diablo or SCT. Problem is I remember speaking to someone who supplied the conversion kit fot me and he told me that thr hemi jk ecu is locked meaning the programmer wont sync with the ecu. Is that a true statement? If so,, how the hell can i bypass the lock ?!

 

Hey what's your gas mileage? I have a 6.4 hemi 2dr manual 14/15 city and 17/18 highway with 35" tires. I don't think you can tune it cause at least from my understanding and my jk it was specially tuned from Burnsville offroad.

 

Wtf!? That's better than my '14 wk2 6.4 srt! I get 12-13 city and 14-16 highway without being aggressive. I have better aerodynamics and numerically lower gears lol. I'm coming back to the jk world as soon as my gc gets hit by an asteroid and all that's left is the motor to swap into the jk lol.

 

Haha no way really? I thought I was lacking mpg's. You know having a JK is fun but having a JK with a motor swap is a whole other kind of fun. I'm pushing 470 Hp in my jk.

 

What gears are you running ??yep got the same tune

 

I have 4:10s. I asked dan at Burnsville offroad if I could use the superchip for the tire size and he said strictly only for that otherwise you'll screw up the tune I think. I never did it since it wasn't worth 150$ for just a tire calibration and didn't want to take the chance.