Patent ID: 8415283

Claim:
A diesel engine system running on diesel fuel with not more than 10 mass ppm sulfur, comprising a regenerative diesel particulate filters (“DPF”) and a lubricant comprising a lubricant composition as an engine lubricant, said lubricant composition comprising: a lubricant base oil, and additives including: (A) a metal detergent including at least one of alkaline earth metal salicylate and an overbased or basic salt thereof, (B) an ashless dispersant comprising both a boron-containing ashless dispersant and a boron-free ashless dispersant, and (C) a phosphorus-based anti-wear agent consisting of metal mono- or dihydrocarbyl phosphate, wherein said lubricant composition satisfies all of the following conditions (1) to (4): (1) a sulfated ash content of 0.4 to 1.2 mass %, (2) an atomic ratio of metal derived from component (A) to the total phosphorus (M/P ratio) of 0.4 to 2, (3) an atomic ratio of the total boron to metal derived from component (A) (B/M ratio) of 0.2 to 2, and (4) an atomic ratio of the total sulfur to metal derived from component (A) (S/M ratio) of 0 to 4, and wherein the composition does not include a thiophosphate.