Universal (all-weather) oil

All-weather oil must be used for BMW engines. Multigrade oils have the advantage that they operate over a wide temperature range (summer Winter). The basis of all-weather oil is a grade of liquid oil (e.g. 15W). The so-called hot thickener stabilizes the oil. thus retaining its lubricating properties under all operating conditions. When using multigrade oils, modern grades with a wide temperature range of viscosity should be chosen (e.g. 15W-40, 15W-50).

Letter "W" in the SAE designation indicates the suitability of the oil grade in winter.