MoparPartsGiant.com offers the wholesale prices for genuine 2019 Ram ProMaster 3500 parts. Parts like Fuel Rail are shipped directly from authorized Mopar dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 4 Cyl 3.0L Diesel, 6 Cyl 3.6L. Transmission: 6-Speed Automatic Transmission.