GMPartsGiant.com offers the wholesale prices for genuine 1999 Chevrolet C3500 parts. Parts like Engine Assembly-Oil Pump, Pan & Related Parts are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 8 Cyl 5.7L, 8 Cyl 6.5L Diesel, 8 Cyl 7.4L. Model Code: C3500 CAB CHASSIS 135.5, C3500 CAB CHASSIS 159.9, C3500 CAB CHASSIS 183.5, C3500 CREW CAB LONG WHEELBASE, C3500 CREW CAB SHORT WHEELBASE, C3500 EXTENDED CAB, C3500 REGULAR CAB.