What is the difference between 5w and 10w?

[OFinley]

The main functions of engine oil are to reduce friction and wear of moving parts, and to remove sludge (one of the functions of dispersants) and paint (cleaner) from the engine. The differences between 5w and 10w are as follows: 1. Different low-temperature working capabilities: 5W has stronger low-temperature working capability than 10W. If you are in the colder northern regions, choose 5W or 0W, while in the southern regions, 10W or 5W are both acceptable. 2. Different sales prices: The price of 10W-grade engine oil is slightly cheaper than that of 5W. 3. Different low-temperature fluidity: W stands for winter, and the smaller the number before it, the better the low-temperature fluidity (engine oil dilution) of the engine oil. Therefore, in terms of low-temperature fluidity, 5W is better than 10W. 4. Different protection capabilities for the engine during cold starts: 5W represents that the engine oil can work at a minimum temperature of minus 30 degrees Celsius; 10W represents that the engine oil can work at a minimum temperature of minus 25 degrees Celsius.