What grade is SM engine oil?
2 Answers
SM engine oil quality grade is second only to SN, and it is also one of the three most common grades of engine oil currently available. Engine oil grades: 1. Definition: API grades represent the quality grades of engine oil. It uses simple codes to describe the working capability of engine oil. Engine oil grades are classified into SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL, SM, and SN grades. The further back the letter is, the higher the grade. 2. Highest grade: SN grade is currently the highest grade of engine oil. SJ was the standard in the 1990s, SL was the standard in 2001, SM was the standard in 2004, and SN was the standard in 2010. Therefore, SM is only one grade lower than SN, and its oil quality is quite good. Most international brand engine oils are above SF grade.
SM oil is one of the performance classifications set by the American Petroleum Institute (API), specifically designed for gasoline engines. This classification was introduced around 2004 with the primary goal of enhancing the oil's oxidation resistance, anti-wear capabilities, and detergency/dispersancy properties, helping to reduce carbon deposits and corrosion inside the engine. Compared to older classifications like SL, SM offers better protection and is suitable for vehicle models from 2004 and earlier. While newer classifications such as SN and SP are now available on the market, SM remains a cost-effective choice for older vehicles. When changing oil, I recommend checking your vehicle's owner's manual. If it specifies SM or a similar classification, you can confidently use it to extend your engine's lifespan. Having worked on many older cars myself, I've observed that engines run more smoothly and with reduced noise after switching to SM oil. Regular oil changes, approximately every 8,000 kilometers, are sufficient.
