Gas mileage won't be the first reason the Impala ends up on anyone's shopping list, and the V-6 versions are set to earn EPA ratings a few miles per gallon lower than some other big four-doors.
The EPA has published the Impala's gas-mileage ratings, with the base vehicle coming in at 25 mpg (21 mpg city, 31 mpg highway) and the more powerful V-6 at 21 mpg combined (18 mpg city, 28 mpg highway).
The combined 21-mpg rating for the V-6 falls below the Toyota Avalon's 25 mpg, the V-6 Taurus' 23 mpg combined, and the 23-mpg figure posted by the Hyundai Azera and the Dodge Charger with its new eight-speed automatic. In our first-drive test loop set up by Chevy, the V-6 Impala's indicated economy checked in at 20.3 mpg, tallied after lots of canyon runs and a few stretches of 75-mph interstate.
Four-cylinder versions brighten the picture. We logged 25.1 mpg--right on the nose--for the base 2.5-liter four-cylinder Impala, albeit over a short 20-minute drive covering about 12 miles.
At the top of the fuel-economy list is the Impala Eco, fitted with GM's mild-hybrid eAssist system. The addition of special aero add-ons--dams, spats, and active grille shutters that smooth the nose for better efficiency--lets the Impala Eco equal the 29-mpg combined figure of the Buick Lacrosse that uses the same system. That's better than the 26 mpg of the turbocharged EcoBoost Ford Taurus--but well off the 40-mpg mark set by the Toyota Avalon Hybrid.