The 2004 Buick LeSabre is available as a 4-door, 5-seat sedan. Starting at $26,040, the 2004 Buick LeSabre Custom is powered by a 3.8L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 20-mpg in the city and 29-mpg on the highway. The top of the line 2004BuickLeSabreLimited , priced at $ 32,085 , is powered by a 3.8L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 20-mpg in the city and 29-mpg on the highway.