What is the difference between 5W30 and 0W30 engine oil?
3 Answers
5W30 and 0W30 are engine oil grades, where W stands for winter oil. 0W indicates the oil can flow at -35 degrees Celsius, while 5W indicates it can flow at -30 degrees Celsius. The specific differences between them are: 1. Generally, 0W30 is more expensive than 5W30. 2. 0W30 has a wider applicable temperature range than 5W30. 3. 0W30 is usually fully synthetic oil, whereas 5W30 can be either semi-synthetic or fully synthetic oil. 4. 0W oil makes starting the engine easier in extremely cold or low-temperature weather compared to 5W oil. In other words, 0W oil is easier to start in winter than 5W oil.
I drove in the north for 10 years, and the main difference between these two engine oils lies in their low-temperature fluidity. The 5w30 has a minimum applicable temperature of -30°C, while the 0w30 can handle down to -35°C. When temperatures drop below -20°C in winter, the 0w30 provides noticeably smoother starts, with no engine shaking. However, in high-temperature summer conditions, both have the same viscosity grade of 30, offering similar protection. I found that with 0w30, the engine sound during cold starts is softer, especially noticeable after leaving the car overnight in winter. That said, 0w30 is about 30% more expensive, and if you're driving in the south, it's completely unnecessary.
When the mechanic taught me about engine oil grades, he said the smaller the number before W, the better the low-temperature fluidity. 5W30 can handle cold starts at -30°C, while 0W30 can go down to -35°C. In northern regions with winter temperatures below -30°C, 0W30 lubricates faster during cold starts. However, once the engine warms up, there's no difference as both have the same high-temperature viscosity grade of 30. I've noticed that 0W30 usually has better base oil quality with superior cleaning performance – even after 5,000 km, my engine still sounds smooth. But for daily driving, 5W30 is perfectly adequate unless you live in Northeast China or frequently drive in extremely cold regions.
