GMPartsGiant.com offers the wholesale prices for genuine 2006 Cadillac CTS parts. Parts like Radio Mounting are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 2.8L, 6 Cyl 3.6L, 8 Cyl 6.0L. Model Code: 4 DOOR, 4 DOOR RHD, V 4 DOOR.