Can all-season engine oil be used in winter at -30 degrees Celsius?
2 Answers
All-season engine oil can be used in winter at -30 degrees Celsius. Engine oil selection: When choosing engine oil, it's not about selecting the most expensive one, but rather about choosing the most suitable oil based on your car engine's characteristics and your usual driving habits. You can categorize your selection by choosing oil for winter use and oil for summer use. For winter, the primary consideration is the low-temperature viscosity grade. In summer, when temperatures are high, there's no need to select oil with a better low-temperature viscosity grade. Engine oil grades: Engine oil grades are divided by quality level and viscosity grade. Oil for gasoline engines is usually marked with the letter "S", while oil for diesel engines is usually marked with the letter "C".
When I was young, I worked as a driver in Northeast China, where winter temperatures often dropped to -30°C. I've used many all-season engine oils, like 5W-30, which generally perform well in such extreme cold. The key factor for engine oil in severe cold is its flowability; if it thickens too much, starting the car becomes difficult and can damage the engine. From my experience, when buying engine oil, pay attention to the W rating on the bottle—the lower the number, the better the flowability. For example, 0W is more reliable. Not all brands work equally well; I’ve tried some off-brand oils that thickened at just -20°C, making morning starts impossible. To be safe, I installed a small heater in the garage or switched to winter-specific oil. If you use all-season oil long-term, check it regularly and replace it before winter to ensure proper lubrication and avoid engine failure.
