Low temperature kinematic viscosity is not necessarily better with higher viscosity, and its advantages and disadvantages need to be comprehensively judged based on specific application scenarios (such as brake fluid or lubricating oil) and usage environments.‌‌

Brake fluid scenario

Low temperature kinematic viscosity directly affects the response speed of the braking system. The lower the viscosity, the better the low-temperature fluidity, and the shorter the brake pedal stroke in cold environments,The ABS/ESP system responds more sensitively. For example, the kinematic viscosity of DOT4 brake fluid at -40 ℃ needs to be lower than 1500mm ²/s. If the viscosity is too high, it may cause braking delay or even failure. Competitive vehicles may choose high viscosity brake fluid to enhance high-temperature protection, but daily use needs to focus more on low-temperature responsiveness. ‌‌

Lubricating oil scene

For engine lubricating oil, low temperature kinematic viscosity (such asThe smaller the number before W in the SAE standard, the better the cold start performance. Low viscosity engine oil has good fluidity at low temperatures and can be quickly pumped to the friction surface, reducing start-up wear and power loss. If the viscosity is too high, it will make it difficult to start at low temperatures and increase the engine running resistance, leading to an increase in fuel consumption. For example, in cold regions, it is recommended to use 0W or 5W grade engine oil, while high viscosity protection should be emphasized in high-temperature environments. ‌‌

Choose Suggestions

‌brake fluidPriority should be given to selecting products with low-temperature viscosity that meets national standards (such as DOT4 grade -40 ℃ viscosity<1500mm ²/s) to ensure low-temperature braking sensitivity. ‌‌

‌lubricating oilSelect SAE low temperature viscosity grade (such as 0W, 5W) according to the climate, and low viscosity engine oil should be used in cold regions to ensure cold start performance. ‌‌

‌balance performanceHigh and low temperature viscosity should be taken into account, for example, multi-stage oil (such as 10W-30) can adapt to a wide temperature range and avoid pursuing high viscosity alone.