What is the grade of SJ engine oil?
3 Answers
SJ grade is one of the API quality grades, corresponding to engine oil specifically for gasoline vehicle engines. The SJ standard was established in 1996, making it over twenty years old, and is considered a relatively outdated engine oil grade that is gradually being phased out or upgraded. SJ oil does not belong to the category of semi-synthetic oils and is essentially mineral oil. Below is more information about engine oil grades: 1. Quality Grades: API classifies engine oils into the S series and C series, with the S series indicating oils specifically for gasoline vehicle engines. 2. Gasoline vehicle engine oil models include SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL, SM, SN, and SP, with the latest being the SP grade, which is several grades above the SJ level.
I've been running an auto repair shop for over 30 years and know engine oil grades inside out. The SJ designation is a standard classification for gasoline engines set by the American Petroleum Institute (API), dating back to the late 1990s. In the oil classification sequence, 'S' stands for gasoline engine oils, with later letters indicating newer standards - SJ ranks between SH and SL, officially introduced in 1997. Older vehicles still on the road today, like vintage Jettas and Fukangs over 20 years old, have engines particularly well-suited to SJ-formulated oils. This grade offers better oxidation resistance than SH and more reliable high-temperature cleaning performance. While most new oils today meet the SP standard, some mechanics still keep SJ-grade oil for servicing classic cars. Always check the original manufacturer's manual before changing oil to avoid clogging delicate oil passages in older engines.
Recently, I helped my cousin with the maintenance of his '97 Accord and happened to research the SJ grade. It belongs to the API (American Petroleum Institute) gasoline engine oil standard, a product standardized in the mid-90s. In the oil grade sequence, from low to high, it goes SA, SB... up to the latest SP, with SJ positioned in the mid-to-late range. Compared to its predecessor SH, it enhanced sludge resistance and volatility control, and also reduced phosphorus content to protect the catalytic converter. However, mainstream oils on the market have long since upgraded to SN and SP, so finding SJ requires digging through old stock at auto parts stores. It might still be worth using for cars manufactured before 2000, but remember not to mix it with modern oils.
