A - For high power and easy flowing oils (all-season with anti-friction additives). According to VW standards 50000 and 50500
B - All-season oils. According to VW 50101 standards, only for petrol engines
C - Seasonal oils
Since the application areas of adjacent SAE classes overlap, short-term temperature fluctuations can be ignored. It is permissible to mix oils of different viscosity classes with each other if it is necessary to top up the oil and the outside air temperature no longer corresponds to the viscosity class of the oil in the engine.
Additional additives, no matter what their properties, cannot be added to either fuel or oil.
In the CIS countries, a different designation of viscosity classes is used. Below is a table that can be used to select the appropriate oil.
Viscosity grade matching
(The original article is located on the online resource: AUDImanual)