Choosing the best coolant for your car is an important aspect of proper car ownership. As temperatures rise your car circulates a mixture of water and coolant to prevent a meltdown from inside the engine.
For such an important role a well-tested coolant and one recommended by the manufacturer is of utmost importance for a long-lasting engine. To answer this question one should be acquainted with all the different types of coolants out there, but the best option is the coolant that came with your Mercedes Benz from the factory.
Traditional Coolants
Traditional coolants are backed by (IAT) Inorganic Acid Technology, mostly suited for protecting many different iron components of an engine due to the usage of silicate and phosphate corrosion inhibitors.
As most newer Mercedes models and many other German manufacturers started using aluminum for the majority of different engine components, an IAT backed coolant is not recommended. For older models though, IAT coolants were usually the recommended ones.
IAT coolants are also a lot less efficient, as the service intervals between IAT-backed coolants are a lot shorter compared to OAT’s for example. Furthermore, IAT coolants require a lot more monitoring to ensure all the corrosion inhibitors are at a correct level.
All coolants ought to be drained and flushed from time to time as per the manufacturer’s recommended intervals. And in such scenarios, the sheer disadvantages of IAT back coolants are also apparent as they tend to mask up the leaks in the system by clogging up the holes.
¸HOAT/OAT coolants
HOAT coolants are derived from Hybrid Organic Acid Technology, mostly suited for protecting various aluminum parts of your engine. As most German manufacturers including Mercedes have moved towards favoring aluminum for the engine construction, these types of coolants are the ones usually recommended by the manufacturer.
OAT backed coolants do not use phosphate inhibitors nor silicates, and are developed with a 5-year long usage in mind, or around 150k miles. Even though these do function for a period of 5 years, most manufacturers still recommend doing flushing every 2 years or so.
Furthermore, these coolants are recognized as non-toxic, as such they offer bio-degradable properties and they do not pose any environmental or health and safety issues compared to traditional (ITA) coolants.
Mixing coolants
Mixing different types of coolants is possible, and it should not pose any major risks for the engine’s durability and reliability. But, it is certainly not advisable to do so, as mixing different types of coolants could reduce the effectiveness of the resulted mixture.
If you mix OAT and IAT coolants, all the benefits of OAT coolants in the properties that do manage to extend the life of OAT coolants will cease to exist. It is advisable to leave such tasks to trained professionals because a continuous improper usage of coolant might prove to be a problem for keeping your engine at its optimum.
If you do end up mixing, try to make sure that the mixture ratios are in significant favor of the type of coolant recommended for your automobile. As older cars mostly use IAT coolants, and if you use OAT in such automobiles all the corrosion inhibiting properties will be gone and your engine will not be managed as recommended.
FAQ Section
How can I find out which coolant is recommended for my car, and which color should I choose?
If you want to know which coolant is recommended for your car, you should check your owner’s manual. Most car manufacturers go to great lengths to provide a lengthy piece of information about the coolant for a specific car in the owner’s manual.
If you don’t have the manual, then you can always ask your local car dealer or service department for further information. Or even check online from credible sources, but be aware that in many cases such sources might just be a marketing hub for a specific coolant manufacturer.
As far as color is concerned, using the same color as your original coolant is always going to be the best option. Coolants come in many different colors, and the color is mostly for being able to distinguish different types of coolants.
Most OAT coolants are colored orange, bright red, blue, or dark green, and most HOAT coolants are colored yellow, pink, blue, or purple colors. But this should never be the mean upon which you differentiate the two.
The truth is that most coolants are clear and are only later dyed for distinguishment purposes, but be aware that these colors don’t always match and that you should always consult a professional before choosing any particular coolant.
How often should I replace my coolant?
As mentioned previously OAT/HOAT coolants are tested to function properly as long as 5 years, and most IAT coolants are only good for around 2 years. While these numbers are true, these can be easily affected by many different variables in a specific ownership experience, so you should follow the guidelines recommended by the manufacturers.
Some manufacturers even offer a specific blend of coolant that can withstand life-long usage. Now, for this information, you should also check your owner’s manual or consult a licensed dealer or service department of your manufacturer.
How to dilute my coolant?
Changing your coolant is not something you should do if you are not completely informed about all the ins and outs of specific coolants and the needs of your vehicle. But, if you decide to give it a shot you should be aware that diluting the coolant with water is necessary if your coolant is not already pre-diluted.
For most cases, a 50:50 ratio should do the trick, but for extremely low temperatures such as less than -36°C (-34°F), you should opt for a mixture ratio that favors coolant 70:30. The water should not be regular tap water as it contains many different minerals that might affect the corrosion properties.
The best option would certainly be de-ionized or distilled water for a perfect mixture that will ensure that your engine runs at optimum condition no matter the weather conditions.
