Antifreeze is concentrated ethylene glycol with anti-corrosion additives that prevent freezing and corrosion of the cooling system, and increase the boiling point of the coolant.
Therefore, the engine cooling system must be filled with the mentioned aqueous antifreeze solution all year round.
Due to the fact that the content of anti-corrosion additives in the coolant decreases over time, it must be changed as part of the vehicle maintenance, see chapter «Maintenance».
The coolant should also be changed when installing new aluminum parts of the cooling system, for example, a cylinder head or a water pump.
The system should only be filled with antifreeze recommended by Mercedes, for example, «Glysantin Protect Plus/G482».
Attention! On sale there is a silicate-containing antifreeze, determined by the blue-green color, and antifreeze without silicates. The latter is red. These two types of antifreeze must not be mixed. This can cause significant engine damage.
The ratio of water and antifreeze must be maintained in a ratio of 1: 1, which is considered «correct». In this case, frost protection must be ensured at temperatures down to at least -37°C.
Antifreeze should be mixed with clean water of drinking or distilled quality.
To provide freeze protection down to -45°C, the coolant must be 55% antifreeze and 45% water.
Attention! The proportion of antifreeze content in the coolant should not exceed 55%. Otherwise, the useful effect of the coolant is reduced.