What is the optimal amount of engine oil to add to a car?

[VanSophia]

When adding engine oil, it is generally advisable to fill it between the upper and lower marks on the dipstick, and not below the middle mark. This is because high-speed driving can cause the engine to heat up, making the oil thinner. If the oil level is too low, it can reduce lubrication and cooling efficiency. Here are some key considerations when selecting engine oil: 1. Choose according to the engine's requirements: There's no need to use high-grade oil in engines with lower requirements, nor should lower-grade oil be used in engines that demand higher specifications. 2. Consider the temperature: If the engine is in good condition and the seasonal temperature is low, it's best to use oil with lower viscosity to ensure smooth oil flow. In high-temperature seasons or when the engine is severely worn, using higher viscosity oil helps form a protective oil film and reduces engine wear.