InfinitiPartsDeal.com offers the wholesale prices for genuine 2012 Infiniti M56 parts. Parts like Rear Final Drive are shipped directly from authorized Infiniti dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 3.7L, 8 Cyl 5.6L. Grade/Trim: Base, Premitec, Premium, Premium Touring Tech, SportPre, SportTec.