The coloration of engine coolant serves as a visual indicator of its type and condition. Different manufacturers employ distinct dyes to differentiate their formulations, aiding in proper selection and preventing mixing incompatible chemistries. For example, a bright green fluid commonly signifies a traditional Inorganic Additive Technology (IAT) coolant, while orange or pink often indicates an Organic Acid Technology (OAT) formulation.
Correct coolant selection is crucial for optimal engine cooling and corrosion protection. Using the wrong type can lead to reduced cooling efficiency, accelerated corrosion of engine components, and ultimately, engine damage. Historically, coolants were less diverse in color, but the increasing variety of engine materials and cooling system designs has led to a proliferation of specialized formulations, each identified by a specific hue.