Why Car Coolants Have Different Colors and Which One You Should Use
Coolant is also antifreeze and, therefore, essential for the proper functioning of the engine. But not all are the same and they can be distinguished by color. We explain what each one indicates so you won't get confused when you go to buy it.
Antifreeze not only prevents the engine from freezing in winter: it is a vital element to keep it at the proper temperature all year round. Without it, the engine would operate under extreme conditions that would drastically shorten its lifespan.
However, when you go to check the level in the car or you approach the store to buy a jug, it's easy to wonder: why are there coolants/antifreezes of so many different colors?
In this article, I explain what each shade means, what aspects you should consider before filling the cooling circuit, and how to avoid mistakes that can be very costly.
What is coolant really?
Coolant is mainly composed of distilled water and glycols (ethylene glycol or propylene glycol) in different proportions. In addition, there are corrosion inhibitors, anti-foaming agents, and lubricants designed to protect the circuit against oxidation and the formation of deposits (this already indicates that using only water is not a good idea).
Its mission is not simply to cool, but also to maintain the engine temperature around 90 °C, preventing both overheating and freezing in cold climates. Therefore, the conclusion is that without antifreeze, the engine would be doomed to seize sooner or later.
The colors of coolant: much more than aesthetics
The striking color of coolant is not a whim of manufacturers to differentiate brands, but a practical way to quickly identify the type of mixture and additives it contains.
| Color | % Distilled Water | % Antifreeze | Main Characteristics |
|---|---|---|---|
| Pink | 50 | 50 | Balanced, common in many modern cars |
| Green | 60 | 40 | Good protection against corrosion |
| Blue | 70 | 30 | Excellent heat absorption, more expensive |
| Yellow | 80 | 20 | More economical, lower durability |
The blue is considered the highest quality and is usually used in high-performance cars, but the most common in conventional cars is pink, especially among European manufacturers. As a general rule, all fulfill their cooling function, but durability and corrosion protection vary.
Does each manufacturer use a different color?
Exactly. Although the table above helps to guide, there is no universal color standard. For example:
- Volkswagen and Audi usually use pink antifreeze.
- BMW and Mazda opt for green or blue.
- Renault uses yellow.
Additionally, hybrid vehicles tend to use two different liquids: pink for the thermal engine and blue for the electric part. Therefore, before relying solely on color, it is best to consult the manufacturer's manual or the label on the container.
CONSEJO Motor.ES
The golden rule is not to mix colors, respect the type recommended by the manufacturer, and perform periodic changes
Never mix colors, it can be a very costly mistake
One of the most common mistakes in home maintenance is filling the circuit with a color different from what the car already has. It may seem like a minor detail, but mixing antifreezes with different additives can cause:
- Formation of solid deposits that obstruct the radiator or water pump.
- Loss of anticorrosive properties, with the risk of damaging the engine block.
- Accelerated oxidation of the circuit.
If you are not sure which one your car has —because over the years it can turn brown or cloudy— the safest thing is to add distilled water until a complete change is made.
How often should coolant be changed and how much does it cost?
Coolant does not last forever. Although it may seem intact at first glance, the additives degrade over time.
In cars with timing belts, it is common to replace it along with this (about 100,000 km). In cars with timing chains, the interval is usually longer (up to 200,000 km). If you do not reach that mileage, it is advisable to change it every four years.
Keeping the liquid in good condition is just as important as an oil change: ignoring it can lead to a repair costing thousands of euros.
The price depends on both the brand and the type, but generally, a five-liter jug costs between 8 and 16 euros.
Here it is advisable to avoid overly cheap brands: a saving of a few euros can turn into a disappointment of 2,000 if the engine overheats.
So now you know, the color of antifreeze is not just a matter of aesthetics, but a practical code to differentiate compositions and properties.
The golden rule is not to mix colors, respect the type recommended by the manufacturer, and perform periodic changes. This way, the engine will remain protected, efficient, and have a longer lifespan.