Field Performance Of Factory-Installed Anti-Freeze Coolants In Passenger Car Service

Four annual surveys have been conducted to determine the condition of factory-installed anti-freeze coolants during typical consumer usage after both one or two years of service. Over 25% of the cars required preventive or corrective cooling system service within the first year, and this increased to 47% or more in the second year. Dilution of the coolant with water in many cars reduced both freezing protection and corrosion protection, often to unsafe levels. The modern anti-freeze coolant is capable of providing satisfactory year-round service in a leak-tight cooling system when accompanied by periodic cooling system inspection and preventive maintenance where required. However, many coolants do not give the anticipated service because of mechanical factors, inhibitor depletion from natural causes, and the practices of service men and car owners.