GMPartsGiant.com offers the wholesale prices for genuine 2011 Cadillac CTS Wagon parts. Parts like Horn are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 3.0L, 6 Cyl 3.6L, 8 Cyl 6.2L. Model Code: 4 DOOR WAGON, 4 DOOR WAGON(RHD), V 4 DOOR WAGON.