OER Parts offers a wide selection of Heater Parts for your 1974 Buick Century. OER Parts offers 1974 Buick Century Expansion Valve, 1974 Buick Century Hose Clamps, 1974 Buick Century Hose Fittings, 1974 Buick Century Hoses and Lines, 1974 Buick Century Vent and Duct Parts.