This paper investigates an oxidizing catalytic converter in a diesel engine's particulate filter system, focusing on simulations and empirical studies. The converter, with a 1.4 dm3 volume and 400 cpsi channel density, features a platinum coating of 2.5 g/dm3. Scanning electron microscopy (SEM) examined its surface, revealing platinum and a highly porous structure with randomly distributed Pt crystallites. Simulations were conducted using AVL Boost, utilizing real exhaust gas concentrations to assess various converter volumes and channel densities for CO, HC, and NO2 conversion in NOX. These simulations were paralleled with empirical tests on an engine dynamometer. The comparison of simulation and experimental data showed that the simulation algorithm could accurately predict the converter's performance in reducing CO and HC levels and NO2 in NOX. This suggests that simulations can partly replace costly empirical research, offering a preliminary evaluation of the converter's future effectiveness.