Reason no. 347 why the Chevrolet Sonic is not to be confused with the forsaken outgoing Aveo: the Sonic will actually get better gas mileage than vehicles larger than itself. For example, take the old Aveo’s rating of 35 mpg on the highway compared to the larger, late Chevy Cobalt, which achieved up to 37 mpg highway. It seemed that the frugal Aveo was pointless in that regard if you think about it. In fact, our own Alex Luft observed a dismal combined 18 MPG during his time with the subcompact. As for the Sonic, GM expects it to achieve the coveted 40 mpg mark right off the bat, bypassing the larger Chevy Cruze (non ECO) model’s mark of 36 MPG.
The main reason behind the improved efficiency of the Sonic compared to the Cruze (despite both vehicles sharing the exact same transmission and 1.4L boosted ECOTEC engine) include the noticeable difference of roughly 500 pounds in weight reduction. This would put the Sonic in an exclusive club of non-hybrid gas misers that includes its rival, the Ford Fiesta. In fact, the Sonic manages to attain 138 horsepower to the Fiesta’s 120.
And here’s one to top things off: when we asked Jim Federico at the 2011 North American International Auto Show about the Sonic’s expected fuel economy, he hinted that it could be better than that of the Cruze Eco, which returns a lofty 42 MPG on the highway. Let’s hope so…
Source: Kicking Tires