MoparPartsGiant.com offers the wholesale prices for genuine 2015 Ram 1500 parts. Parts like Pick-Up Box are shipped directly from authorized Mopar dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 3.0L Diesel, 6 Cyl 3.6L, 8 Cyl 5.7L. Transmission: 6-Speed Automatic Transmission, 8-Speed Automatic Transmission.