The 2011 Buick LaCrosse is available as a 4-door, 5-seat sedan. Starting at $27,130, the 2011 Buick LaCrosse CX FWD is powered by a 2.4L , 4 -cylinder engine mated to an automatic transmission that returns an EPA estimated 19-mpg in the city and 30-mpg on the highway. The top of the line 2011BuickLaCrosseAWD , priced at $ 33,205 , is powered by a 3.6L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 16-mpg in the city and 26-mpg on the highway.