What is the Difference Between Winter and Summer Engine Oil?

[DanteFitz]

Viscosity differs, with winter engine oil having lower viscosity and summer engine oil having higher viscosity. Below is relevant information: 1. Winter vs. Summer Comparison: Winter temperatures are low, and using oil with excessively high viscosity can lead to insufficient fluidity, increasing engine wear and resistance. Summer temperatures are high, and using oil with excessively low viscosity can result in inadequate lubrication. 2. Introduction to Viscosity: The effectiveness of engine oil relies on an important characteristic—viscosity. The oil must possess viscosity properties to provide a protective film for various engine components. Generally, viscosity refers to the physical property of the oil (while the viscosity index is a physicochemical indicator of the base oil), originally meaning the ease with which a fluid or semi-fluid flows, commonly referred to as "thick" or "thin."

[VanGraham]

I've been driving for transportation for over a decade and have personally experienced the nuances of changing engine oil. The difference between winter and summer oils mainly lies in viscosity and temperature adaptability. Winter oils have a 'W' in their grade, such as 5W-30, where 'W' stands for winter. The smaller the number, the better the low-temperature fluidity, ensuring the oil doesn't freeze even in temperatures as low as minus ten degrees Celsius. In summer, you need oils with a higher second number, like 10W-40, which maintain sufficient viscosity at high temperatures to prevent thinning and failure. I remember one year when I skipped changing the oil for convenience, and the engine made terrible noises while climbing hills in the scorching heat. Later, I learned it was because the oil couldn't withstand the high temperatures, and the oil film couldn't hold up. Nowadays, most oils on the market are multi-grade, like 5W-30, which can be used year-round, but in extremely cold regions, 0W oils are more reliable. The viscosity specified in the maintenance manual is the most accurate—don't switch randomly.

[EleanorLee]

This is a common question we encounter at auto repair shops. The key difference between winter and summer oils lies in their SAE viscosity grades. Winter oils use low-temperature viscosity grades, such as those starting with 0W or 5W, which have good low-temperature pumpability and can quickly lubricate critical components like the camshaft during cold starts. Summer oils, on the other hand, require high-temperature viscosity grades, such as SAE 40 or 50, to prevent insufficient oil pressure due to thinning under high temperatures. Multi-grade oils like 5W-40 are designed to balance both needs. However, it's crucial to note that long-term use of the wrong viscosity can accelerate wear. Northern drivers should never use a summer oil with a 20 viscosity grade in winter—I once repaired a car that suffered cylinder scoring because of this. Most modern cars now use universal oils like 5W-30, but in extreme climates, it's essential to choose based on local temperatures.

[CatherineRose]

I learned this from the mechanic during my last maintenance. The difference between winter and summer engine oils mainly lies in fluidity and protection. Winter oils like 0W-20 flow like water at low temperatures, ensuring smooth starts even at -30°C. Summer oils such as 15W-40 are thick like honey at high temperatures, preventing engine friction from overheating. Most cars now use multi-grade oils like 5W-30, which work well in both winter and summer. However, driving habits matter: cars frequently driven short distances in winter need lower viscosity oil, while those driven long distances at high speeds in summer require higher viscosity oil. Choosing the wrong oil may increase fuel consumption by 3% or even damage the catalytic converter. It's recommended to refer to the temperature range chart on the oil container based on your regional climate.

[SimonLynn]

Last winter during my self-drive trip in Northeast China, I did some thorough research. The most crucial aspect of winter engine oil is its low-temperature performance. The number before the 'W' indicates cold-start capability—0W can flow at -35°C, while 5W works down to -30°C. For summer, focus on the number after 'W'; for instance, 30 represents viscosity at 100°C. I use 5W-30 oil, which suffices for Beijing's winters and summers, but in Mohe, I'd switch to 0W-20. Some older cars benefit from higher-viscosity oil in summer to reduce oil consumption, but it can harm newer engines. Remember, oil containers usually have temperature range diagrams—check local historical temperatures before purchasing. Nowadays, full synthetic oils generally offer broader adaptability, eliminating the need for frequent seasonal oil changes.