The 2017 Buick LaCrosse is available as a 4-door, 5-seat sedan. Starting at $32,065, the 2017 Buick LaCrosse Base FWD is powered by a 3.6L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 21-mpg in the city and 31-mpg on the highway. The top of the line 2017BuickLaCrosseAWD , priced at $ 43,265 , is powered by a 3.6L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 20-mpg in the city and 29-mpg on the highway.