Filling the cooling system with antifreeze (Audi A4 B6)

For reliability, even in summer, you should use a mixture containing at least 40% antifreeze. However, if you frequently add only water, the concentration of antifreeze may be insufficient for low temperatures. In addition, this lowers the boiling point of the liquid. In this case, you need to add G12 antifreeze. To do this, you first need to drain some of the coolant. The amount of liquid drained depends on how much antifreeze is actually contained in the coolant, and how much antifreeze should be contained in it after topping up.

If, due to climatic conditions, it is necessary to provide stronger protection against freezing, then the proportion of antifreeze can be increased, but not more than to 60% (in this case, protection will be provided up to approximately minus 40 degrees), since with a further increase in the proportion of antifreeze, protection worsens.

To ensure frost protection down to -25°C, the proportion of antifreeze should be 40% (3.2 l G12 and 4.8 l water), for protection up to -35°C the proportion of antifreeze should be equal to 50% (4.0 l G12 and 4.0 l water). These values are valid for a coolant volume of 8.0 l, depending on the vehicle equipment, this volume may be different.

1. Remove the soundproofing cover from the bottom of the engine and place a clean container under the radiator (engine) to collect the spilled liquid.

2. Drain the appropriate amount of coolant.

3. Slide on and secure the hose.

4. Add the required amount of antifreeze to the expansion tank. If necessary, add the collected liquid.

Information obtained from this resource AUDImanual.ru