Depends on the terrain. (hills and such) Mine is more than 2 years old and we've made many trips. If no hills to speak of, close to 24 MPG. With hills (such as from Louisville, KY to North Georgia) we average 21 to 22 MPG. Hope this helps.
ideally it won't take more than 25 mpg. but at a high speed as 110 km it would give less speed. http://goo.gl/NNl5w
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