Will using 5w40 engine oil harm a new car?
2 Answers
Using 5w40 engine oil in a new car will not harm the vehicle. However, due to its higher viscosity and poorer fluidity, it may affect the operation of the new car's engine, thereby increasing fuel consumption. Overall, it does not have a negative impact on the car. The symbol 'W' stands for Winter, and the number before 'W' indicates the oil's low-temperature flow performance, while the number after 'W' represents the oil's high-temperature viscosity. Engine oil, also known as engine lubricant, consists of base oil and additives. The base oil is the main component of the lubricant, determining its basic properties, while additives compensate for and improve the shortcomings of the base oil, providing certain new properties, making them an important part of the lubricant.
I previously researched the issue of engine oil for new cars and felt that using 5W40 oil in a new car wouldn't directly damage it, but it might not be the optimal choice. New car engines are designed with precision, and generally, low-viscosity oils like 0W20 or 5W30 are recommended. These oils reduce internal friction, improve fuel efficiency, and protect engine longevity. If you use 5W40, the higher viscosity increases resistance, leading to slightly higher fuel consumption and making the engine work harder during cold starts in winter. I think short-term use might not cause issues, but over time, it could increase wear risks or lead to higher fuel costs. Check your car's manual—it will definitely have the recommended oil specifications. If you accidentally use the wrong oil, don't panic; just switch to the appropriate one at the next service. Maintaining a regular oil change routine is most important—new cars are most vulnerable to neglect in maintenance.
