Over the last three decades or so, Mercedes has used three different coolant variants in their gasoline and diesel-powered cars. The oldest is Q1030002, a Yellow or Gold-colored G05 HOAT formula that is no longer available through Mercedes. It may still be available in small quantities through manufacturers like Zerex, but Mercedes recommends you drain and refill with a more modern variant. Switching from G40 to G13 coolant involves more than simply adding the new coolant to your vehicle’s cooling system. It is important to follow the proper procedures to ensure that the new coolant is compatible with your engine and that all of the old coolant is removed. OATs, HOATs, and Si-OATs, am I right? I know that sounds confusing, but you don't need to know the chemical makeup of every fluid in your car; that's an engineer's job. What you do need to know is which coolants can be used together. Carrying around spare fluids is a nice thought, but not everyone has the space for them, so knowing which coolant types that can top off your system in a pinch can save your cooling system. G13 contains some silicate additives for that additional healing aluminium protection. This is contrary to some earlier specifications that use OAT-technology (Organic Acid Technology). Silicate additives make G13 ideal for long-term use in all modern radiators, especially those constructed from aluminium, cast iron and magnesium alloys. The Swedes are either hated or loved for their odd choices and unique style. But when it comes to engine coolant, Volvo has remained consistent. Their only coolant formula is that of a G48-type. G48 Coolant

The boiling point of G13 coolant is 175°C (347°F), while that of G40 coolant is 170°C (338°F). The boiling point indicates the temperature at which the coolant boils, which can cause the engine to overheat if the boiling point is too low. Manufacturer Recommendation Due to G12 no longer being made, if the system needs a top-off, it is not recommended to mix antifreeze types. A drain, flush, and re-fill are suggested with the latest fluid. All other coolant forms are still in production and can be found with ease. With that said, updating to the most modern coolant isn't a bad idea. It's the best blend of corrosion-inhibiting organic additives and lubricating silicates.

Following this maintenance schedule will ensure the prolonged life of your cooling system. Below is a radiator with clogged ports due to the build-up of silicate. This can lead to an overheating engine, so consider the perceived cost-benefit you get from skipping coolant flushes versus the cost of a new engine.

Next to protection against freezing, the G13 is also excellent for cooling and protection against corrosion and chalk deposits. Coolant as we know it today, also called antifreeze, is a kind of “super water.” Within it are many chemical compounds, the most important being Glycol. When added to water, Glycol raises the boiling point and lowers the freezing point, stabilizing it for use in almost every application while also containing the lubricants that help the water pump and thermostat function effortlessly. The rest of the chemicals are corrosion inhibitors and dyes (orange, green, red, or blue). The corrosion inhibitors are critical to the type of material that the engine is made from and are categorized into four different types. Engine Coolant Corrosion Inhibitors: G13 coolant is pink in color, while G40 coolant is yellow. The color of the coolant does not affect its performance but can help identify the type of coolant used in the engine. Freeze Point

Engine Coolant Compatability

Therefore, it is important to use the recommended coolant for your specific vehicle and to never mix different types of coolant. It performs best at high temperatures and prevents the engine from being destroyed by heat caused by combustion and friction.

The G13 has a purple/violet colour and has the same exceptional cooling and antifreeze performance as G12++. The main difference: it is manufactured using glycerin instead of glycol. Glycerin is much less harmful to the environment than glycol. One is a bi-product of biodiesel production, the other is produced from mineral oil. G12 Evo is now required in all VW Group vehicles, this is the most up to date, latest version of coolant from VW Group. G12 EVO is the latest correct coolant and replaces G12, G12+ & G13, it may have been made after your car was built (this will be the reason it may not appear in your handbook/manual, or on the coolant cap itself) G05andG48 are compatible with each other, regardless of color. However, we advise a switch to G48 after performing a full cooling system drain, flush, and re-fill, due to current availability.Once you have chosen the correct coolant, you can fill the cooling system with the new coolant. You should follow the manufacturer’s instructions for the correct ratio of coolant to water, which is usually 50/50. The newer OAT coolants work a bit differently than the older silicate-based IAT coolants. First off, these coolants don't have any silicates or phosphates. They contain organic salts to protect the cooling system. This means that their service life is extended. This category of antifreeze cannot be used in systems containing yellow metals, meaning older cars with copper and brass cooling system components can not use this type of coolant. Newer cars with aluminum engines and cooling system components are mostly OK. The corrosion inhibitors make up the bulk of the various chemicals within the coolant. The four main types all use different compositions, giving them different properties suited to different cooling systems. Reason 2: Mixing different types of coolant can also reduce the effectiveness of the coolant, which can cause your engine to overheat and potentially cause damage. G13 coolant is recommended by Volkswagen, Audi, and Porsche, while G40 coolant is recommended by Mercedes-Benz and BMW.

Both G13 and G40 coolants have a freeze point of -37°C (-34°F), making them suitable for use in cold climates. The freezing point indicates the temperature at which the coolant freezes, which can cause engine damage if not suitable for the climate. Boiling Point The manufacturer’s recommendation is based on the specific requirements and characteristics of the engine, and using the recommended coolant can help ensure proper engine performance and longevity. How to switch from G40 to G13 coolant? Step By Step It is estimated that the manufacturing of G13 produces 11 % lower CO2 emissions than antifreeze with glycol. By avoiding silicates, G40 coolant like – Zerex G40 is able to provide better protection and lubrication for your engine over the long term.As critical as those different formulas are, they aren't regularly referred to by them. Instead, the largely accepted naming scheme comes from BASF. As one of the largest chemical producers in the world, BASF's Glysantin line of engine coolants is largely used as a general differentiator between coolant types. Their naming scheme is the originator of the G05, G40, and G48 designation, among others. Below, you'll find those Glysantin product names attached to each respective manufacturer's coolant specifications for ease of understanding. Engine Coolant Types VW GROUP Coolant Anti Freeze G12 evo replaces G12 plus AND G13 This bottle replaces the 1.5 Litre Bottle (G013A8JM1) This fluid is also for: Antifreeze is the hidden hero of our car’s engines. If you don’t know how antifreeze works, it’s pretty simple. Antifreeze is added to the water in your engine’s cooling system that lowers its freezing point (and raises its boiling point too). It’s why the liquid in your radiator doesn’t freeze when everything else seems to be! You can choose a concentrated coolant that needs to be mixed with water or a ready-mixed one that can be used immediately. About our Antifreeze and Engine Coolant If you are unsure about which type of coolant to use, it is always best to consult your owner’s manual or a qualified mechanic for advice. By using the correct coolant for your vehicle, you can ensure that your engine is protected and running smoothly. Genuine G12evo (new version of G13) coolant additives protect individual engine components, safeguarding the engine’s long service life. It contains substances that form a protective coating against corrosion, helping to prevent foaming and neutralise ‘hard’ water ie water with a high mineral content.