What is the normal color of engine oil?
2 Answers
Different brands of engine oil have different colors. Common engine oil colors include transparent colorless, light yellow transparent, brown transparent, red transparent, green transparent, and blue transparent. Relying solely on color to determine whether engine oil is normal is not a scientific method. Generally, if the engine oil appears clear, it is normal. If the engine oil appears cloudy, it is abnormal. Below is more information about engine oil: 1. Engine oil is divided into two main categories: mineral oil and synthetic oil. Synthetic oil is further divided into semi-synthetic oil and full synthetic oil. Among them, full synthetic oil is of the highest quality, followed by semi-synthetic oil, while mineral oil is of the lowest quality. 2. Under normal circumstances, full synthetic oil should be replaced approximately every 10,000 kilometers or once a year; semi-synthetic oil should be replaced approximately every 7,500 kilometers or every 8 months; and ordinary mineral oil should be replaced every 5,000 kilometers or every six months.
When I first started driving, I was really curious about how engine oil changes color. Now, with more experience, I understand. Fresh oil poured in is clear and bright, like freshly brewed honey water—a light yellow or amber color, very pleasing to the eye. After driving a few thousand kilometers, it gradually darkens to brown or black, which is normal because the oil is working to clean carbon deposits and impurities from the engine. However, be cautious if it turns as black as ink in a short time or develops milky foam or a watery consistency—this could indicate issues like coolant mixing in or oil burning, requiring immediate inspection. I usually check the dipstick color every 5,000 km; if it stays clear or moderately discolored, the engine runs smoothly. Oil color changes are so intuitive—it's like a car's health barometer. Don’t wait until it’s too dark to change it, or the engine noise may increase, and damage could occur. Regular maintenance saves hassle and money. When changing oil, choose a reputable brand—don’t skimp. With normal oil color, the car runs longer and more reliably.
