New Crankcase Lubricants for Heavy-duty Diesel Engines: Effect on Fuel Consumption and Exhaust Emissions

The effect of crankcase lubricant on fuel consumption and engine exhaust emissions was investigated. Seven different lubricants were measured in a 9.6-liter bus engine, representing Euro 2 emission-level technology. The measurements were made using six different steady-state load conditions. In addition to fuel consumption measurements, gaseous and particle mass emissions and particle size distribution measurements were performed.

The average difference between the worst and the best lubricant on fuel consumption was 1.6%. There was a clear correlation between the viscosity of the lubricant and the fuel consumption. Also, changes in total hydrocarbons and particle mass emissions occurred. The differences ranged between 0.6 to 22%.