The 2017 Lexus RX 450h is available as a 4-door, 5-seat sport utility. Starting at $53,035, the 2017 Lexus RX 450h Base is powered by a 3.5L, 6-cylinder engine mated to an automatic transmission that returns an EPA estimated 31-mpg in the city and 28-mpg on the highway. The top of the line 2017 Lexus RX 450h F Sport, priced at $56,495, is powered by a 3.5L, 6-cylinder engine mated to an automatic transmission that returns an EPA estimated 31-mpg in the city and 28-mpg on the highway.