Chevy Impala Hybird

 Automotive spy photography firm Brenda Priddy & Co. caught GM engineers testing the Eco version of the Impala.

The Impala Eco will offer a four-cylinder engine, mated to a low-energy hybrid system, with an anticipated 35 mpg in highway driving.

The 10th generation of the Impala will go on sale early 2013 as a 2014 model, and this will be the first to offer a mild hybrid powertrain system in the shape of what GM calls eAssist.

The prototype caught in pictures, wears a newly styled grille with styling cues linking to the Chevy Volt’s grille. Aside from this new grille and the “Eco” badge on the trunklid, the prototype does seem to be style-wise just like its regular, non-hybrid version.

This mirrors the strategy used by Toyota for its Camry lineup, where the hybrid version is details apart visually from its regular sibling.

The revised Impala will be built both at GM’s Detroit-Hamtramck, Mich., and Oshawa, Ontario facilities. Prices have yet to be announced.