Can I Use 5w30 Instead of 5w40?
5w30 and 5w40 refer to the viscosity grades of motor oil. Viscosity measures the oil’s resistance to flow, with lower numbers indicating thinner oil and higher numbers indicating thicker oil. 5w30 oil is thinner than 5w40 oil, so it flows more easily at low temperatures. 5w40 oil is thicker, so it provides better protection at high temperatures.