GMPartsGiant.com offers the wholesale prices for genuine 2021 Cadillac XT4 2WD parts. Parts like A/C Refrigeration System are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 4 Cyl 2.0L. Model Code: ALL PURPOSE 4 DOOR BASE, ALL PURPOSE 4 DOOR LUXURY, ALL PURPOSE 4 DOOR SPORT.