Can antifreeze of the same color be mixed?
2 Answers
Whether antifreeze of the same color can be mixed depends on the situation: 1. If the color is the same and the main components are almost identical, they can be mixed; 2. If the color is the same but the main components differ significantly, they should not be mixed, as this could cause a chemical reaction. The main components of antifreeze are ethylene glycol, propylene glycol, and diethylene glycol. Ethylene glycol is generally green, propylene glycol is red with a hint of orange, and diethylene glycol is blue. The reasons for antifreeze having different colors are: 1. To distinguish between different ratios of antifreeze—both water and antifreeze agents are colorless, making it impossible to differentiate different ratios by eye, so different dyes are added for distinction; 2. To clearly identify leaks in the antifreeze and help easily locate the leak point; 3. To easily monitor the consumption of antifreeze in the radiator and replenish it in time; 4. To prevent accidental ingestion and make it easy to distinguish from water.
I've been a car mechanic for 15 years and seen too many cases where people mix coolants just because they're the same color. Even if both are green coolants, formulations vary drastically between brands. When ethylene glycol-based meets organic acid technology (OAT), the mismatched pH levels can completely neutralize the corrosion inhibitors. Last week, a car owner mixed two green coolants - three months later, the radiator connections were leaking like a sieve. The safest approach is checking the container label for 'OAT' or 'HOAT' markings. In emergencies, you can top up with distilled water up to 15% ratio, but replace the entire system ASAP. The cooling system is the engine's lifeline - never improvise cocktail mixtures.
