MoparPartsGiant.com offers the wholesale prices for genuine 2020 Ram 2500 parts. Parts like Rear Wheelhouse Shields are shipped directly from authorized Mopar dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 6.7L Diesel, 8 Cyl 6.4L. Transmission: 6-Speed Automatic Transmission, 8-Speed Automatic Transmission.