The Study of Friction Modifiers to Improve Fuel Economy for WLTP with Low and Ultra-Low Viscosity Engine Oil

Applying friction modifier (FM) in low viscosity engine oil is one well known cost effective approach for improving a fuel economy of vehicles. At first, the characteristics and mechanisms of FMs on tribological phenomena were studied with surface analysis technics. The performance of FMs was also evaluated with engine component test and motored engine test to understand the friction property of FMs in engine application. Then the effect of driving cycle, lubricant viscosity and FMs in fuel economy performance under chassis dynamo were studied.

Among tested FMs, molybdenum dialkyl dithiocarbamate (MoDTC) was the most effective at boundary lubrication, which is considered significantly important friction area for WLTP, latest procedure for fuel economy test, with low and ultra-low viscosity engine oil.