Buick will offer its redesigned base model LaCrosse CX with a new fuel-efficient, direct injected Ecotec 2.4-litre four-cylinder engine priced at $26,995 in the first quarter of 2010. The I4 is the third engine choice for the all new 2010 model line and, with six-speed automatic transmission, is expected to deliver fuel economy of 30mpg highway and 20mpg city- making the new Buick one of the most fuel-efficient cars in its segment.