Welcome, and Semper-Fi. When it comes to modern diesels with DPF systems, there is not a whole lot you can do to modify the exhaust. The pipe(s) are designed in a way to allow for the best possible cooling and airflow at the same time, which is important because when in a regen, the exhaust temps get VERY hot. That is why since the DPF came out you see larger exhaust tips. At least on the 6.6. Not sure about the 3.0.