Which engine oil covers the largest range of temperatures?

You chose answer 1 (SAE 10 W 40), which is correct. SAE 10 W 40 is a multigrade oil, meaning it performs well in both low and high temperatures. The "10 W" indicates it works like an SAE 10 oil in winter (cold conditions), ensuring good flow at low temperatures, while the "40" means it behaves like an SAE 40 oil when hot, providing protection at higher engine temperatures. Compared to SAE 10 W 30 or SAE 30, SAE 10 W 40 covers a broader temperature range, making it suitable for more varied climate conditions and temperature changes throughout the year. Understanding oil grades helps you choose the right oil for your vehicle, ensuring consistently good engine lubrication and protection.