How to Check Engine Oil Viscosity?
2 Answers
To check engine oil viscosity, look for the oil grade and viscosity rating on the oil bottle, collectively referred to as the oil specification, along with the oil classification. Taking 0W20 as an example: The 0W in 0W20 indicates the oil's cold-start performance. Using oil with a lower number before the W makes it easier to start the engine in cold weather. The 20 in 0W20 represents the oil's viscosity characteristics at high temperatures. Engine oil, motor oil, or engine lubricant is a substance enhanced with additives in base oil, primarily containing anti-wear additives, detergents, dispersants, and multi-grade oil viscosity index improvers.
My experience with changing engine oil is that viscosity is mainly checked through the label on the oil bottle, which displays numbers like 5W-30 or 10W-40. The first part, such as 5W, indicates low-temperature performance—the smaller the number, the more fluid the oil is in cold weather, making it easier to start the engine. The latter part, like 30, represents high-temperature viscosity—the higher the number, the better it resists heat. Every time I buy new oil, I glance at the label to ensure it matches my car manual's requirements, such as using a lower number for northern winters. It's also important not to buy the wrong viscosity, as an unsuitable grade can cause engine stalling or even damage. During regular oil changes, I also check the oil level with the dipstick—if the oil is too dark or thin, it's time for a change. Developing this habit helps prevent premature engine aging and saves on repair costs.
