The 2018 Lexus RX 350 is available as a 4-door, 5-seat sport utility. Starting at $43,470, the 2018 Lexus RX 350 Base FWD is powered by a 3.5L, 6-cylinder engine mated to an automatic transmission that returns an EPA estimated 20-mpg in the city and 27-mpg on the highway. The top of the line 2018 Lexus RX 350 F Sport AWD, priced at $50,520, is powered by a 3.5L, 6-cylinder engine mated to an automatic transmission that returns an EPA estimated 19-mpg in the city and 26-mpg on the highway.