I have 328xd 2014. I use Carly and was looking at the codes. I was looking at 244800 code I think stating that the filter needs attention. There is 150K on the clock. I think it is telling me that the filter needs to be replaced. I was hoping for a third party provider of the part as it is about 1500.00 for the part alone. Add the labor, well it gets rather expensive. Is there a third party to get the part from? Is there anything else that can be done such as a cleaning? What other parts should I replace when this service done as a PM? Lower/ upper Nox sensors, gaskets clamps? Any advice