The 2014 Infiniti QX50 is available as a 4-door, 5-seat sport utility. Starting at $34,850, the 2014 Infiniti QX50 Base 4x2 is powered by a 3.7L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 17-mpg in the city and 25-mpg on the highway. The top of the line 2014InfinitiQX50Journey AWD , priced at $ 38,600 , is powered by a 3.7L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 17-mpg in the city and 24-mpg on the highway.