MoparPartsGiant.com offers the wholesale prices for genuine 2003 Jeep Wrangler parts. Parts like Water Pump are shipped directly from authorized Mopar dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 4 Cyl 2.4L, 6 Cyl 4.0L. Transmission: 4-Speed Automatic Transmission, 5-Speed Manual Transmission.