OER Parts offers a wide selection of Cooling System Components for your 1979 GMC All Models. OER Parts offers 1979 GMC All Models Molded Radiator Hoses, 1979 GMC All Models Upper Radiator Hoses, 1979 GMC All Models Lower Radiator Hose, 1979 GMC All Models Water Pump Bypass Hose, 1979 GMC All Models Oil Cooler to Radiator Hose, 1979 GMC All Models Throttle Body to Radiator Coolant Hose, and 1979 GMC All Models Universal Engine Coolant Plumbing Set.