Gas Mileage Not As Great As One Might Think

Story first appeared in USA TODAY.
Chevrolet's new small Sonic subcompact is going to be able to join the 40-mile-per-gallon club, but only with a pricier, turbocharged version.
Despite GM's earlier claims of a 40-mpg rating for the 2012 Chevrolet Sonic, the standard 135-horsepower, 1.8-liter four-cylinder will be rated by the EPA at 26 miles a gallon on the highway and 35 mpg on the highway, for a combined 29 mpg with a five-speed manual transmission. With an optional six-speed automatic transmission, the 1.8-liter returns 25 city/35 highway/28 combined mpg.
The only way to get 40 mpg on the highway is to opt for the 138-horsepower, turbocharged 1.4-liter four-cylinder, which comes with a six-speed manual transmission only. The engine is a $700 option for the higher level LT and LTZ trims. The Sonics are starting to boom their way into dealers: Cars.com shows more than 500 Sonics available, but none are equipped with the turbocharged motor just yet.
The Sonic's EPA rating is a disappointment compared with its competitors and even against its larger sibling, the Cruze:
A 2012 Chevrolet Cruze equipped with the same 1.8-liter four-cylinder and a six-speed manual transmission gets 25 city/36 highway/29 combined mpg. The Cruze Eco with an automatic transmission gets a 26 city/39 highway and 31 mpg combined. The fact that the lighter-weight Sonic scores no better than a Cruze is probably due to aerodynamics.
Competitors like the 2012 Hyundai Accent (30 city/40 highway mpg), 2012 Ford Fiesta SFE (29 city/40 highway mpg), 2012 Toyota Yaris (30 city/35 highway mpg) and 2012 Honda Fit (28 city/35 highway mpg) all score better. To add insult to injury, the Sonic scores worse, or no better, than the outgoing 2011 Chevy Aveo, which got 27 in the city and 35 on the highway for a 30 mpg combined with a manual transmission and a combined 28 mpg with a four-speed automatic transmission.
We don't know if GM plans on releasing an Eco version of the Sonic, which would help it compete with other fuel misers. For now, the model will likely try to compete on price since it's behind the field on mileage.
The 2012 Chevy Sonic went on sale earlier this month.