What are the differences between antifreeze of different colors?
3 Answers
Different colors of antifreeze indicate different types. In fact, the color is caused by adding dye to the liquid, which is only used to distinguish it from other liquids and has no other special functional purpose. It also helps users distinguish when choosing antifreeze to prevent mixing different types of antifreeze, which could damage the engine. The functions of antifreeze: Antifreeze is a coolant containing special additives, mainly used in liquid-cooled engine cooling systems. It has excellent properties such as preventing freezing in winter, boiling in summer, and protecting against scale and corrosion throughout the year. Can different antifreeze be mixed? The same brand of antifreeze must be used. Different brands of antifreeze may have different production formulas. If mixed, chemical reactions may occur between multiple additives, causing them to become ineffective. How to choose antifreeze: The basic indicators of antifreeze are freezing point and boiling point. On the market, antifreeze comes in several specifications with freezing points of -15°C, -25°C, -30°C, -40°C, etc. Generally, it is advisable to choose one with a freezing point at least 10°C lower than the lowest temperature in your region. Antifreeze plays an important role in long-distance vehicle driving.
When I first started maintaining my car myself, I was curious about how to choose between different antifreeze colors like green, blue, and red. Later, I learned that the colors represent different formulations. Green is typically the traditional silicate type, suitable for older cars, offering good cooling performance but prone to degradation. Red or pink belongs to the organic acid technology (OAT) type, ideal for newer vehicles, with strong anti-corrosion properties and a long service life. Blue or yellow might be hybrid types, compatible with various engine types. Remember not to mix different colors, as this can cause chemical reactions leading to blockages and damage to the cooling system. Check your car's owner manual for recommendations or ask a mechanic to use the same type—it's both hassle-free and protects your engine. Personally, I change it every two years, ensuring the color matches to avoid any issues.
As a long-time car owner, I've witnessed the wisdom behind coolant color coding. Green indicates basic inorganic acid formulas, commonly used in pre-1990s vehicles; orange and red represent newer organic acid technologies with enhanced corrosion protection for modern aluminum components; blue sometimes denotes specific long-life products. The colors aren't decorative but serve as warnings about formula differences - mixing can cause sedimentation, clog pipes, or even corrode radiators. I always advise friends to note their vehicle's factory color when purchasing and maintain consistency during replacements, warning against careless mixing for convenience or cost savings. Regular checks of fluid levels and color changes can prevent major repair headaches.
