InfinitiPartsDeal.com offers the wholesale prices for genuine 2011 Infiniti FX50 parts. Parts like Front Seat Belt are shipped directly from authorized Infiniti dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 3.5L, 6 Cyl 3.7L, 8 Cyl 5.0L. Grade/Trim: Base, Premium, Sport.