| abstract |
A lubricating oil composition which comprises a lube base oil and contains 5 to 5000ppm by mass of a 3,4,5-trihydroxybenzoic acid ester and 0.001 to 10.0% by mass of a phosphorus compound, each content being relative to the lubricating oil composition. The lubricating oil composition can prominently reduce wear. Further, the lubricating oil composition can ensure a low and stable coefficient of friction and has a high rust-preventive effect on an iron-based sliding part. Therefore, the lubricating oil composition is suitable for long-term use, and exhibits a prominent energy-saving effect by virtue of the low and stable coefficient of friction. |