The 2009 Acura MDX is available as a 4-door, 7-seat sport utility. Starting at $40,990, the 2009 Acura MDX Base is powered by a 3.7L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 15-mpg in the city and 20-mpg on the highway. The top of the line 2009AcuraMDXTechnology Pkg w/Entertainment Pkg , priced at $ 46,790 , is powered by a 3.7L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 15-mpg in the city and 20-mpg on the highway.