MoparPartsGiant.com offers the wholesale prices for genuine 1991 Dodge W350 parts. Parts like Tailgate are shipped directly from authorized Mopar dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 3.9L, 6 Cyl 5.9L Diesel, 8 Cyl 5.2L, 8 Cyl 5.9L. Transmission: 3-Speed Automatic Transmission, 4-Speed Automatic Transmission, 5-Speed Manual Transmission, 8-Speed Automatic Transmission, Open.