MoparPartsGiant.com offers the wholesale prices for genuine 1999 Dodge Durango parts. Parts like Plugs Floor Pan 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, 8 Cyl 5.2L, 8 Cyl 5.9L. Transmission: 4-Speed Automatic Transmission.