The 2012 Chevrolet Cruze will improve fuel economy by 2 highway mpg over the 2011 model, when equipped with the 1.4L turbo engine and six-speed automatic transmission.
This means the 2012 Cruze will get 38 mpg on the highway (Versus 36 on the 2011 model), but the 24 mpg city rating will remain the same. Chevy has achieved this by lowering the gearbox’s final-drive ratio from 3.87 to 3.53, allowing the engine to run at a lower speed and therefore use less fuel. However, such a change could harm acceleration and responsiveness.
Other changes to the 2012 Cruze include the expanded availability of a manual transmission to more trim levels, and new exterior colours.
Source: 2012 Chevrolet Cruze Online Ordering Guide via Cheers and Gears, Green Car Reports