Can Antifreeze from Different Brands Be Mixed?
2 Answers
Antifreeze from different brands cannot be used together. The production formulas of antifreeze vary by brand, and mixing them may cause chemical reactions between the various additives, leading to their ineffectiveness. Antifreeze Replacement Cycle: Vehicle antifreeze generally needs to be replaced every 2 years or 40,000 kilometers. This is just a reference period. For commercial vehicles with higher mileage, the replacement cycle should be shorter. Since driving conditions vary for each vehicle, the replacement should be based on actual usage. Check the antifreeze's condition—if it is insufficient, replenish it promptly. If suspended particles, sediment, or signs of deterioration or discoloration are observed, replace the antifreeze and clean the system immediately. What Is Antifreeze? The full name of antifreeze should be antifreeze coolant, meaning a coolant with antifreeze properties. Antifreeze prevents the coolant from freezing and cracking the radiator or damaging the engine cylinder block or head during cold winter parking.
I used to drive for several years and once mixed different brands of coolant, which resulted in the engine temperature skyrocketing. That time, I added some red-label coolant into the green-label one, thinking they were all the same. Within a few days, the cooling system got clogged. The mechanic said it was due to significant differences in formulations—additives like silicates and organic acids reacted when mixed, forming sediment. It cost me hundreds to clean it up. Since then, I’ve stuck to one brand and regularly check the fluid level and color. Coolants are divided into traditional IAT and long-life OAT types; mixing them may neutralize the anti-corrosion effect, potentially damaging internal engine components due to corrosion. It’s best to thoroughly flush the system when replacing the coolant annually and only top up with small amounts of the same brand. Lesson learned—don’t cut corners for convenience, safety comes first when driving.
