OER Parts offers a wide selection of Heater Parts for your 1972 GMC All Models. OER Parts offers 1972 GMC All Models Expansion Valve, 1972 GMC All Models Hose Clamps, 1972 GMC All Models Hose Fittings, 1972 GMC All Models Hoses and Lines, 1972 GMC All Models Vent and Duct Parts.