Took a short trip mainly by Interstate of several hundred miles and checked my NITRO’s highway mileage for the first time. Fairly impressed, since it averaged 19.6 for the whole trip with the A/C on. One thing I did notice was it did not like 75 MPH and lost about 1 MPG over driving 60 MPH. This I suspect will change in the future when Chrysler has a 6 speed AT like my Wife’s Ford V-8 SUV, instead of the present 5 speed in my R/T. Adding a sixth speed is like adding a overdrive gear that really increases mileage at a higher highway speed. Think I read that Ford plans to use only 6 speeds in the future to increase their mileage and Chrysler should follow suit. I also am very pleased with it's ride at 75/80 MPH with no vibrations. Again, I am glad I bought it, not only for it's looks!