Low viscosity engine oils: Study of wear effects and oil key parameters in a heavy duty engine fleet test

Abstract Low viscosity engine oils (LVO) are considered key contributor for improving fuel economy in internal combustion engines (ICE). Attending that the use of LVO could imply a variation in tribological states found in ICE, this work׳s aim is to test LVO in real fleet, with emphasis on engine wear and oil key performance indicators. This test comprised 39 buses, two engine technologies and four different lubricants. For each sample, the elemental composition of the wear debris by ICP-AES and HTHS viscosity of the oil were measured among other properties. The results showed that, with a correct oil formulation, there is no significant difference when using LVO in terms of engine wear, HTHS viscosity variation and oil consumption.