FordPartsGiant.com offers the wholesale prices for genuine 2005 Mercury Montego parts. Parts like Rear Seat Back are shipped directly from authorized Ford dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 3.0L DOHC EFI Modular. Transmission: 6-Speed Automatic Transaxle - AWF21, CVT Select Shift Transmission.