Optimization of the oil drain interval of non-phosphorus and non-ash engine oil

Abstract

Purpose Zinc dialkyldithiophosphate (ZDDP) is the most common anti-wear and anti-oxidant additive. ZDDP is the primary origin of zinc, sulfur and phosphorus, which are well-known poisonous elements for commercial after-treatment systems. The aim of this study is to investigate the optimum oil drain interval of non-phosphorus and non-ash (NPNA) engine oil that was developed as a prospective alternative to commercial phosphorus-containing (PC) engine lubricants. Design/methodology/approach The results of a fleet test wear debris analysis were used to optimize the oil drain intervals from the perspective of cost. Findings Drain intervals of 32,000 and 28,000 km were computed as the optimum values for NPNA and PC engine oils, respectively. Extending the oil drain intervals up to the obtained mileage may go to a total saving of €43,045,084.2 for PC engine oil and €49,253,998.6 for NPNA engine oil with respect to the total sales figures of test vehicles in Turkey. Originality/value Maximizing the lubricant life has environmental benefits and is the easiest way to reduce the maintenance cost of a vehicle. The protection of after-treatment systems against lubricant-induced poisoning is a great challenge. The most important result of this investigation is the lower operation costs of catalyst-friendly lubricants in spite of their low anti-wear additive performance.