A vehicle engine must always have sufficient lubrication. The protective lubricating film reduces the mechanical friction of the moving components and prevents metal from making contact with metal. Without oil, the engine would suffer serious damage within seconds. The correct motor oil must guarantee lubrication under all operating conditions and loads that occur in the engine.
A regular oil change increases the service life of the engine and transmission. Over time, the motor oil is consumed and soiled, for example due to thinning with fuel or condensation water, natural oil aging and mechanical abrasion.