| abstract |
Provided is a method for using a lubricating oil composition in which the content of a metal-based cleaning agent (X) having a base value of 100 mgKOH/g or less is 630 mass ppm or less in terms of metal atoms, and the content of sulfated ash is 1.5 mass% or less, the method comprising a step for measuring at least one physical property value among the capacitance and the dielectric constant of the lubricating oil composition while using the lubricating oil composition, and evaluating the progress of degradation of the lubricating oil composition. |