OER Parts offers a wide selection of Cooling System Components for your 1969 Buick GS 400. OER Parts offers 1969 Buick GS 400 Molded Radiator Hoses, 1969 Buick GS 400 Upper Radiator Hoses, 1969 Buick GS 400 Lower Radiator Hose, 1969 Buick GS 400 Water Pump Bypass Hose, 1969 Buick GS 400 Oil Cooler to Radiator Hose, 1969 Buick GS 400 Throttle Body to Radiator Coolant Hose, and 1969 Buick GS 400 Universal Engine Coolant Plumbing Set.