Which is better between SL and SN engine oil?
2 Answers
Engine oil grades are classified into SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL, SM, and SN levels. The later the letter in the alphabet, the higher the grade, with SN being the highest grade of engine oil currently available. Therefore, SN-grade engine oil is superior to SL-grade engine oil, and the higher the grade, the better. Here is some information about engine oil: 1. API (American Petroleum Institute) is the abbreviation for the American Petroleum Institute. The API grade represents the quality grade of engine oil. It uses a simple code to describe the working capability of engine oil. 2. Engine oil grades are classified into SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL, SM, and SN levels. The later the letter in the alphabet, the higher the grade, with SN being the highest grade of engine oil currently available. 3. SJ is the standard from the 1990s, SL is the standard from 2001, SM is the standard from 2004, and SN is the standard from 2010.
I've been studying motor oil standards, and both SL and SN are API classifications, but SN is the newer standard. Simply put, SN is definitely better, with upgrades in three main areas: stronger protection for turbocharged engines, especially needed by modern small-displacement turbo cars; lower sulfur and phosphorus content, which extends the life of the catalytic converter; and improved oxidation resistance, increasing oil life by about 20%. However, owners of older cars shouldn't worry too much—if your car was made before 2005, SL is perfectly adequate and cheaper. My old Accord has been running on SL oil all along. But for new cars, always use SN, especially for models with direct injection or turbochargers.
