Which viscosity grade should I choose ?

Huile Moteur Quelle Viscosite

The viscosity of lube oils is expressed with a cold grade (number before the letter W) and a hot grade (for example: 10W40). The higher the numbers, the higher the viscosity. Thus, an oil with a low grade will allow fuel economy by limiting friction while a high grade will allow the formation of a thicker film between moving parts for better protection.

In the case of an engine oil, you must refer to the manufacturer’s recommendations when choosing the viscosity grade.