Can fully synthetic engine oil be changed once every year and a half?
2 Answers
No. Generally, the replacement interval for fully synthetic engine oil is one year or 10,000 kilometers. Here is some extended knowledge about engine oil: 1. Classification: mineral oil, semi-synthetic oil, and fully synthetic oil. The classification is mainly based on the difference in base oils. Typically, mineral oil uses Group II or III base oils, semi-synthetic oil uses Group III or IV base oils, and fully synthetic oil uses Group IV or V base oils. 2. Lubrication performance: mineral oil performs the worst, fully synthetic oil performs the best, and semi-synthetic oil falls in between. 3. Oil change intervals: mineral oil is generally changed every 5,000 kilometers, semi-synthetic oil every 7,500 kilometers, and fully synthetic oil every 10,000 kilometers. If the vehicle has been parked for more than three months, it is recommended to change the engine oil before use.
I'm the type who enjoys maintaining my own car and often researches engine oil. While full synthetic oil is durable, changing it only once every year and a half might be too risky. I've seen many cases where oil absorbs moisture, thickens, and collects debris over time, reducing its lubricating effectiveness. This increases internal engine wear and can double repair costs. Generally, full synthetic oil is recommended to be changed every 6 to 12 months or every 5,000 to 10,000 kilometers, depending on your driving habits. If you frequently take short trips or drive in hot or congested urban areas, the oil degrades faster. It's advisable to check the oil quality during each maintenance session, testing its viscosity or color, and not to delay changes for too long. This protects the engine and saves money.
