Environmental authorities such as EPA, VCA have enforced stringent emissions legislation governing air pollutants released into the atmosphere. Of particular interest is the challenges introduced by the limit on particulate number (PN) counting (#/km) and real driving emissions (RDE) testing; with the Euro 6c emissions legislation being shortly introduced for the gasoline direct injection engines. Gasoline particulate filters (GPF) are considered to be the most immediate solution. While engine calibration and testing over the NEDC allows the limits to be met, real driving emission and cold start represent a challenge. The present work focuses on an experimental durability study on road under real word driving conditions. Two set of experiments were carried out. The first study analyzed a Gasoline Particulate Filter (GPF) (2,4 liter, diameter 5,2” round) installed in underfloor (UF) position driven for up to 200.000 km. A 1.6 liter Direct Injection Spark Ignition (DISI) engine was used for the investigation. Ash accumulation versus mileage and soot loading were of interest. A parallel investigation up to 160.000 km with same engine (2 vehicles on road on a “specific average” cycle) and GPF installed in closed coupled (CC) position was also carried out.The CC GPF was a 2 liter volume with same diameter; the GPF used is a NGK 360 cpsi, 5 mil wall thickness. A 3-D Computational Fluid Dynamics (CFD) analysis is performed to gather information on the fluid flow and pressure loss characteristics of GPF with full length, individual 3-D GPF channels. The Ansys Fluent CFD model was developed and calibrated using the experimental results. Computational domain focuses on two quarters of an inlet and two quarters of an outlet channels with the aim of reducing complexity of the problem and its computational time. Velocity and pressure distributions inside the inlet and outlet channels is of interest. The simulation results are is compared to real data from GPF durability studies.