I have a 05 Cherokee with the Hemi engine that is getting roughly 10-15 MPG. How can I get a guaranteed boost in MPG? I would love to get at least 20mpg.

 

Sell it and buy an econocar. You're around what Hemi's get so...

 

5.8 is your problem. Someone swapped a Ford engine in yours.

 

Shave the mirrors and roof rack, build a bullet nose cone, lower the stance, air the tires up to 60psi, and drive like you have an egg under your foot, you just might make it to 16mpg.

 

It seems to me the 5.7L Hemi wasn't the best choice if fuel economy was a priority. The government says you'll get no better than 18 mpg. My recommendation for improved fuel economy is the same regardless of what you're driving: Proper maintenance, proper tire inflation, no superfluous weight, always clean and waxed, drive at or below the speed limit and take your time getting there. But don't expect much more than 15 mpg, average.

 

With negative equity, there is no point in trading. There are no issues with the vehicle.


What about an ECU Programmer? Has anyone tried one and what were the results?

 

The epa says it gets 13 city and 18 highway and they always are higher then real world.So your 10 to 15 mpg is pretty close only things to help is a full tune up and drive like a old lady.

 

A professional can get you some mpg but enough to cover the cost of the DiabloSport and a tune ... doubt it.