We got our cherokee a week ago. It's the limited version with a 3.2L V6 engine, and 4x4. For the first week of my commute, I only got a 14.0 mpg. The route is basically city and residential. It involves with a lot up-and-downs. The place I work is up on a hill, and the place I live is down the hill.
This past weekend, we had two short road trips, roughly 50 miles one-way. It's 30% highway, 50% national park road, and the rest city. The mpg gets to 23.5.
I did some research and found that the fuel-efficiency would eventually improve when you have a few years into your ownership. They said EPA tests cars with at least 5k miles on its odometer. Now, i have 451 miles on my cherokee. It looks to me that I have to live with this low mpg for a couple of years.