Fuel economy of the 2010 Dodge Challenger. 1984 to present Buyer's Guide to Fuel Efficient Cars and Trucks. Estimates of gas mileage, greenhouse gas emissions, safety ratings, and air pollution ratings for new and used cars and trucks. Coming to a drag strip near you, the 2023 Dodge Challenger SRT Demon 170 has up to 1025 horsepower and a propensity to pop wheelies. EPA Fuel Economy, combined/city/highway (mpg) If the 2014 Dodge Challenger is a terrific representation of muscle-car glory on the outside, it’s sort of merely adequate inside. EPA city/highway fuel economy: 18/27 mpg. 5.7-liter Hemi V8 Search by make for fuel efficient new and used cars and trucks 2014 Dodge Challenger SRT8 8 cyl, 6.4 L, Automatic 5-spd Premium Gasoline: Not Available. For the most part, the Dodge Challenger gas mileage remains the same as last year. Here’s a quick overview of the each model’s fuel economy: Challenger SXT: 19 city/ 30 highway MPG. Challenger GT: 19 city/ 30 highway MPG. Challenger R/T: 15 city/ 23 highway MPG. Challenger R/T Scat Pack: 14 city/ 23 highway MPG. The Scat Pack loses another point because its engine requires premium fuel, whereas the 5.7-liter V8 in the Challenger R/T will accept regular 87-octane gas (although Dodge recommends 89 or 91 tsw7ym.