Root Cause Analysis of High Oil Consumption in 6.4L Heavy-Duty Engines Under Urban Driving Conditions

This paper discusses the high oil consumption in a 6.4L heavy-duty engine for urban driving cycle applications, which is currently in the range of 5,000 to 6,000 miles per quart. This is much worse than that of the highway cycles, which are nearly at 15,000–16,000 MPQ and way below the 26,000 MPQ benchmark that some competing brands have set for similar classes of engines. The research focuses on the specific identification of factors in the city driving cycle that are responsible for high oil consumption and explains these mechanisms. Its purpose is a comprehensive search for root causes that reveal problem areas, provide actionable insights, and solutions. The latter will not only improve oil efficiency but also close gaps in performance to the best in class, particularly across a myriad of challenging city-driving conditions.