Engine coolant is an essential component in maintaining the optimal temperature of your vehicle’s engine. Its unique formulation combines water and glycol to prevent overheating beyond 100°C and freezing up to -40°C. In addition to its thermal properties, this fluid protects against corrosion and extends the life of the engine. To make the right choice, several criteria must be taken into account : color, compatibility with your brand and specific technical standards.
The colour code to be respected according to your vehicle
The range of universal engine coolants ranges from blue to red and pink, with each shade corresponding to a specific technology. Recent vehicles require mostly organic liquids, recognizable by their pink or orange color.
For older models, choose blue or green mineral liquids that are perfectly suited to cast iron engines. German manufacturers often recommend yellow or orange liquids, which are particularly effective for aluminium engines.
The correct type is checked by consulting the maintenance book or examining the expansion vessel. The wrong colour choice can cause limescale deposits and compromise heat exchange in the cooling system.
The specifics of pink engine coolant for Peugeot
The pink engine coolant developed for Peugeot meets the B71 5110 standard, guaranteeing optimum engine protection from -35°C to +107°C. Its unique technology combines organic and mineral additives, providing a longer service life of up to 4 years or 480,000 kilometres.
This special formulation offers increased corrosion resistance thanks to its propylene glycol composition. The anti-scale properties of the pink engine coolant also protect sensitive components in the cooling system, such as aluminum radiators on recent models.
The protective qualities of this liquid are particularly suitable for extreme climatic conditions, whether in hot regions or mountainous areas at risk of frost.
The universal blue and green engine coolant
Blue and green engine coolants are a versatile choice, particularly suitable for engines manufactured before 2000. Their ethylene glycol formulation provides reliable protection against freezing and overheating.
This traditional variant is distinguished by its compatibility with natural rubber seals, common on older models. A major asset lies in its ability to neutralize limestone deposits thanks to its specific corrosion inhibitors.
To maximize its efficiency, check the concentration of the mixture : a proportion of 40% to 50% guarantees optimal performance. French manufacturers such as Renault and Citroën recommend this range for their pre-1995 vehicles.
Yellow and orange for German vehicles
Manufacturers BMW, Audi and Mercedes have adopted yellow and orange engine coolants specially designed for their aluminium engines. G12+ technology integrated in these fluids provides enhanced protection up to 650,000 km without emptying.
These new-generation liquids meet the strict VW TL774 and MB326.0 standards, essential for recent engines equipped with turbochargers. A case in point : the G13 range developed by Volkswagen now offers thermal resistance above 135°C.
The organic additives in these liquids create a molecular barrier on metal surfaces, preventing any build-up of deposits. This innovation significantly reduces the risk of overheating, even under intensive use.
The special high performance red
The red liquid stands out for its exceptional performance on track and in motor racing. Its exclusive formulation with advanced heat transfer agents lowers engine temperature by an average of 10°C under high load.
A concrete example : during endurance races, this type of liquid maintains remarkable thermal stability even after 24 hours of intensive use. The boiling resistance reaches 124°C while the frost protection drops to -32°C.
The latest generation additives create a protective film on metal surfaces while remaining biodegradable. This technology, favoured by the racing teams, is perfectly suited to supercharged engines and high-performance vehicles.
Compatibility by car brand
Volkswagen and Audi specific standards
The VAG group vehicles require strict standards for their engine coolant. The current range includes G12 EVO (VW TL-774-L), developed for models marketed since 2018, and G13 (VW TL-774-J) compatible with previous versions.
The LOBRID PSi-OAT technology, characteristic of these liquids, guarantees an optimal protection of the circuit between -30°C and +107°C. This formulation ensures an increased resistance to high temperatures, particularly suitable for turbocharged engines.
The manufacturer’s recommendations recommend a replacement every 2 to 5 years depending on use. Regular monitoring of the level in the expansion vessel prevents oxidation and maintains the efficiency of the cooling system.
Recommendations BMW and Mercedes
The German manufacturers BMW and Mercedes demand strict standards for their engine coolants. BMW requires the GS 9400 standard while Mercedes imposes the MB 326.0, guaranteeing protection up to -37°C.
For optimal mixing, keep the ratio of 45% to 55% of corrosion protection. Beyond that, cooling properties deteriorate and the frost protection paradoxically decreases.
The LC-87 or LC-97 approved liquids meet BMW specifications perfectly, ensuring an excellent service life of the circuit. Mercedes recommends a concentrate for corrosion protection according to Sheet 310.1 of its lubricant requirements.
Peugeot and Renault standards
Peugeot vehicles use an organic engine coolant specially formulated in accordance with the B71 5110 standard, which ensures increased durability of the circuit. This advanced technology provides enhanced protection for aluminum components, which are very present in modern engines.
On the Renault side, the type D range is distinguished by its exclusive formulation. The selected additives create a particularly effective protective barrier on metal surfaces, reducing premature wear of water pumps and seals.
For maximum performance, the two French manufacturers recommend replacing the liquid every 60,000 km or 4 years. A regular level check in the expansion tank helps to anticipate the risk of overheating and prolongs the service life of the engine.
The composition and standards of engine coolant
The essential anti-corrosion additives
Corrosion inhibitors make up between 4% and 8% of the total coolant composition. These molecules form a microscopic layer on the metal surfaces of the circuit, neutralizing oxidizing agents.
The new generation of organic additives provides protection for up to 5 years or 150,000 km. A striking example : these compounds reduce water pump wear by 60% compared to conventional formulas.
Anti-cavitation agents complement the anticorrosive action by preventing the formation of destructive microbubbles for metals. This technology is particularly suitable for modern engines incorporating aluminium and magnesium alloys.
The G12 standard and its developments
The G12 standard, introduced in the late 1990s, marked a turning point in coolant history. This formulation based on ethylene glycol, without silicates or phosphates, has revolutionized the protection of modern engines.
2005 saw the birth of the G12+ and G12++ versions, offering enhanced durability with thermal resistance ranging from -30°C to +107°C. These developments are distinguished by their characteristic bright pink hue and their ability to preserve aluminum alloys.
For example, a vehicle equipped with G12++ liquid can travel up to 150,000 kilometres before requiring replacement, compared to 60,000 kilometres under the old standards.
The latest generation OAT technology
The Si-OAT technology represents the most advanced evolution of organic coolants. This innovative formulation combines the benefits of organic acids with specially selected silicates for maximum protection of modern alloys.
Car manufacturers now require this technology for their Euro 6 engines, in particular because of its 2.5 times higher corrosion protection capacity than the previous organic generations. A major asset for the overloaded aluminium engines fitted to most recent vehicles.
This new generation is distinguished by the total absence of nitrites, phosphates and borates, making it more environmentally friendly. Its sophisticated formula ensures exceptional stability, even under the most demanding operating conditions of today’s engines.
Practical interventions to be mastered
Safe refilling of liquid
The first golden rule is to wait for the engine to cool completely before any intervention. Once the cover is opened, locate the transparent expansion vessel and its cap, often marked with a thermometer symbol.
Use gloves and a clean cloth to slowly unscrew the cap. This precaution avoids the risk of burns due to possible residual overpressure.
Check the current level between the MIN and MAX marks engraved on the tank. To top up, pour the appropriate liquid gradually into your vehicle using a clean funnel. A handy tip : always keep an emergency can in your trunk, especially on long trips during the summer.
The replacement of brittle hoses
A preliminary diagnosis allows to identify the signs of wear on your hoses : cracks, softened or hardened areas. The presence of air bubbles in the circuit is also a warning indicator.
For effective replacement, start by draining the coolant cold using the purge screw located under the radiator. Then loosen the clamps at the ends of the damaged hose with a suitable clamp.
When installing the new hose, check its compatibility with the manufacturer’s specifications. Precise clamping of the new clamps ensures perfect sealing of the circuit. Gradually fill the system with the correct liquid, then purge the residual air by turning the engine to normal temperature.
How do I know which coolant to use ?
The right coolant can for your needs
The 1-2 litre cans are perfect for occasional use. This reasonable amount allows for easy storage in the trunk of your car for emergency situations.
The 5-litre format is an excellent compromise for forward-thinking motorists. This standard capacity is sufficient for a full oil change on most passenger cars, while guaranteeing an advantageous price per litre.
Professionals and garages prefer the 20-litre capacity, which is particularly economical for intensive use. A practical tip: keep your unopened can in a cool and dry place, away from direct sunlight, to preserve its properties for up to 24 months after opening.
Recommended brands for your car
Premium brands are distinguished by their advanced formulations and extended compatibility with the majority of vehicles. These products provide optimal protection up to -35°C.
Some brands offer a complete range adapted to French vehicles, while others excel in specific liquids for German engines. For Asian cars, some provide enhanced corrosion protection.
Some products stand out for their attractive price-performance ratio while complying with the strictest manufacturer standards. A smart choice for budget-conscious drivers without compromising reliability.
Where to buy coolant ?
Specialized auto centers are a great choice for buying your coolant. These professionals guide you to the right product for your vehicle and often offer additional services such as circuit verification.
Large supermarkets and DIY stores also have a well-stocked automotive department. Their attractive prices and extended hours make it easy to shop. A tip : take a picture of the old can or note its technical characteristics before you move.
Online automotive sales platforms are a practical alternative. Their vehicle model search tools and verified customer reviews help you make the right choice. Home delivery is particularly useful for large packages.
