Is SN engine oil fully synthetic?
2 Answers
SN engine oil is fully synthetic. Fully synthetic SL-grade engine oil is not considered high-quality fully synthetic oil because there are SM and SN-grade fully synthetic oils that perform better than SL-grade. There are even better PAO-based oils, such as imported GT Magic Red engine oil, which surpasses SN-grade and is naturally superior to SL-grade synthetic oil. More details are as follows: 1. SN-grade oils are almost always fully synthetic. 2. Engine oils starting with "S" are specifically for gasoline engines and cannot be used in diesel vehicles. 3. Engine oil grades include twelve levels: SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL, SM, and SN. With each ascending letter, the performance of the engine oil generally improves over the previous grade. 4. Although SN-grade engine oil performs well, it is best to use the grade specified by the engine. If the vehicle is frequently driven in congested urban environments, using a higher-grade engine oil can be more environmentally friendly.
SN in engine oil doesn't mean fully synthetic. It's just a performance grade set by API (American Petroleum Institute) for gasoline engine oils, indicating the oil meets standards in engine protection and wear resistance, especially in helping reduce emissions. Fully synthetic, on the other hand, means the oil is entirely made of molecules synthesized in labs, with pure base oil and good durability, capable of withstanding high temperatures and harsh conditions. Engine oil can be SN-grade fully synthetic, semi-synthetic, or even mineral oil products—the SN label itself doesn't indicate whether it's synthetic or not. I always emphasize this when helping friends choose oil: check the bottle label for the 'Full Synthetic' wording to confirm it's fully synthetic, while ensuring the SN grade matches your vehicle's requirements. This way, you can extend engine life and save on fuel consumption. It's recommended to check the owner's manual for the recommended grade and type during each maintenance to avoid issues caused by using the wrong oil.