Engine oil viscosity refers to how easily oil pours at a specified temperature. Thin oils have lower viscosity and pour more easily at low temperatures than thicker oils that have a higher viscosity. Thin oils reduce friction in engines and help engines start quickly during cold weather. Thick oils are better at maintaining film strength and oil pressure at high temperatures and loads.

Whenever there is an oil change, you have to reset the engine oil system. This is because the engine oil life system is responsible for calculating when engine oil and filter should be changed. In that case, you have to fix oil service light using a diagnostic tool which supports oil reset function.