GMPartsGiant.com offers the wholesale prices for genuine 2014 GMC Sierra 3500 HD 2WD parts. Parts like Automatic Transmission Oil Cooler Pipes are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 8 Cyl 6.0L Flex, 8 Cyl 6.6L Diesel. Model Code: CREW CAB 1 TON, REGULAR CAB 1 TON, REGULAR CAB CHASSIS 1 TON 137.0, REGULAR CAB CHASSIS 1 TON 161.5.