Among the key technologies currently being used for reducing NOx emissions to achieve the target of pollutant emissions (Euro V), Exhaust Gas Recirculation (EGR) has been developed for its effectiveness and its attractive cost for car diesel engines. However, with EGR, more particle matter is emitted from engines. The presence of higher levels of soot in the oil has led to an increase in kinetic lubricant viscosity which in turn could cause lubrication problems and lead to increased wear of engine parts such as cylinder liners, piston rings, valve train systems and bearings, as well as reducing oil drain intervals. SOGEFI developed a specific method to remove soot from oil and has designed a new laboratory test to use several possible configurations and to evaluate the reduction of soot level is described. Characteristics for measuring soot levels and the size of particles are also presented. A filtration solution to decrease soot levels in oil is presented and the results obtained on a diesel engine rig are compared to lab results.