The ASTM D4340-2019 standard provides a laboratory screening method for evaluating the corrosion of engine chill down fluids to cast aluminum alloys under exhaust heat conditions. This test is designed to prevent reduced heat transfer efficiency of aluminum cylinder heads due to chill down fluid corrosion during engine operation, thereby avoiding overheating and boiling of the radiator. The standard can help identify chill down fluids that are not suitable for use with aluminum cylinder head engines, but fail to guarantee long-term performance. To ensure the long-term effectiveness of chill down fluids, a comprehensive evaluation in conjunction with simulation service, dynamometer, and vehicle testing is recommended.