Can 5W20 engine oil be used in summer?
3 Answers
5W20 engine oil cannot be used in summer. The number after W in 5W20 engine oil is 20, indicating a relatively poor viscosity grade. During summer, high temperatures combined with continuous engine operation lead to increased internal temperatures. Engine oil with inadequate viscosity may cause engine damage. 5W20 engine oil is a multi-grade oil. W stands for Winter, the number before W represents the low-temperature resistance index, and the number after W indicates the viscosity index of the oil. 5W means the oil can withstand low temperatures as low as -30 degrees Celsius, meaning this type of oil can still perform its function at -30 degrees Celsius. If the number before W is 10W, it indicates the oil can tolerate low temperatures down to -20 degrees Celsius. In automotive engine oils, the summer oil grades are: 20, 30, 40, 50. The larger the number, the higher the viscosity and the higher the maximum applicable temperature. The winter oil grades are: 0W, 5W, 10W, 15W, 20W, 25W. The symbol W stands for Winter, and the smaller the number before W, the lower the low-temperature viscosity, the better the low-temperature fluidity, and the lower the minimum applicable temperature.
Using 5W20 oil in summer is completely fine. I've been using it in my own car for several years, and it runs smoothly even in high summer temperatures. The '5' before the W represents low-temperature fluidity in winter, and '20' is the high-temperature viscosity index. It can be used as long as the temperature is between -30°C and 35°C. Whether commuting to work or driving on highways on weekends, the engine sound remains steady. However, if you frequently drive in desert areas or haul heavy loads uphill, you might consider switching to a higher viscosity oil. The key is to check your car's manual for recommendations—many Japanese cars specify 5W20. When changing the oil, remember to choose full synthetic for better cleaning and heat dissipation.
I'm quite confident using 5W20 oil during summer as its high-temperature protection is sufficient. The viscosity rating of 20 forms an adequately thick oil film after the engine warms up, and it handles heat dissipation well even in summer traffic jams. I previously drove an American car from Northeast China to Hainan using this grade throughout the journey, and the oil temperature gauge remained consistently stable. Of course, older vehicles might need to consider wear issues - my friend switched his decade-old German car to 5W30. For daily commuting, 5W20 actually saves more fuel than higher viscosity oils, pocketing you a pack of cigarettes worth of savings each month. Just remember to regularly check the dipstick and change the oil early if it darkens.
