GMPartsGiant.com offers the wholesale prices for genuine 2003 Cadillac Escalade EXT 2WD parts. Parts like Block-Underhood BEC are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 8 Cyl 5.3L, 8 Cyl 6.0L. Model Code: EXT 1/2 TON, EXT 3/4 TON.