GMPartsGiant.com offers the wholesale prices for genuine 2005 GMC Sierra 3500 4WD parts. Parts like Generator Mounting 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, 8 Cyl 6.6L Diesel, 8 Cyl 8.1L. Model Code: 3500 CHASSIS EXTENDED CAB 161.5, 3500 CHASSIS REGULAR CAB 137.0, 3500 CHASSIS REGULAR CAB 161.5, 3500 REGULAR CAB.