The numbers are finally in for the gas-saving hybrid technology going into Buick's 2012 LaCrosse, and General Motors says it will result in a 25% fuel mileage boost.


A LaCrosse equipped with the eAssist hybrid system will get 26 miles per gallon in the city and 37 mpg on the highway, GM says. Those are impressive numbers, given the LaCrosse is roomier than midsize sedans that get similar mileage. The smaller, new Buick Regal is also getting the system, but those mileage figures aren't in yet.

The system is basically a streamlined version of a hybrid. It uses a lithium-ion battery, electric motor and regenerative braking capability to improve fuel economy. LaCrosse delivers the fuel economy by making the most of a four-cylinder engine coupled with a six-speed transmission.

"Buick's eAssist technology means customers don't have to trade a premium driving experience for efficiency," said Tony DiSalle, vice president of Buick marketing. "We believe Regal and LaCrosse with eAssist provide more logical and affordable choices, compared to other hybrid midsize and full-size luxury sedans."

Regal with eAssist goes on sale this fall. It joins an expanding lineup that also includes 2.4-liter and 2-liter turbo models, as well as the upcoming Regal GS, a performance model.