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Field inspection of 41 vehicles equipped with magnesium clutch housings or transfer cases was carried out after service in Nova Scotia or Prince Edward Island for periods up to five years. This area is reported to be the most severe location in North America for salt-induced corrosion of automobiles. The die cast magnesium components were unpainted, but basic measures were taken to control galvanic corrosion. The clutch housings had the longest history, with production spanning the years 1982-1987. The general surface corrosion of these housings was negligible, notably less than that of die cast aluminum 380 or carbon steel components on the same vehicle. Slight galvanic corrosion of exposed bolt bosses was observed, induced by the plated bolt. Some galvanic action was noted at the face-to-face junction between the magnesium clutch housings and aluminum 380 transmission cases. This was not sufficiently advanced to indicate a threat to component function.