| 摘要 |
PROBLEM TO BE SOLVED: To obtain a diesel engine oil composition, applicable to even a diesel engine equipped with a diesel particulate filter, excellent in abrasion preventing and cleaning properties, oxidation stability and retention of base number, etc., by blending a specific amount of an additive for a lubricating oil with a base oil. SOLUTION: This diesel engine oil composition comprises a mineral oil and/or a synthetic oil as a base oil, (A) a zinc dialkyl dithiophosphate (e.g. the one represented by the formula) in an amount of 0.04-0.08mass% expressed in terms of phosphorus concentration, (B) calcium carbonate-over based calcium salicylate having 150-200mg KOH/g total base number and/or calcium borate-over based calcium salicylate having 150-200mg KOH/g total base number in an amount of 0.07-0.22mass% expressed in terms of calcium concentration and (C) a boric acid-modified succinimide-based ashless dispersing agent having 2000-5000 number-average molecular weight in an amount of 0.04-0.08mass% expressed in terms of boron concentration. The ash content thereof measured with sulfuric acid is 0.4-0.8mass%. |
