Tech Tip: Maintaining the Diesel Particulate Filter

Vehicles Involved: Vehicles with a V8 diesel engine (2007–2020 models). All Equipped with Diesel Engine RPO L5P, LML, LGH, LUZ, LWN, LH7 or L5D.

Condition:  The DPF is one of three key components of the exhaust aftertreatment system, and works to reduce the amount of particulate matter that remains in the engine’s exhaust gases before they exit via the vehicle’s tailpipe. In general, the DPF is self-cleaning as part of normal operation. When soot in the filter reaches a certain threshold, the Engine Control Module (ECM) will attempt to initiate a regeneration. The self-cleaning occurs approximately once per tank of fuel.
If it’s unable to do so — such as during extended idling or while driving in stop-and-go traffic — and the soot level climbs to a higher threshold, the driver will receive a message on their Driver Information Center (DIC) asking them to continue driving. In these instances, it is recommended that the vehicle be driven above 48km (30 mph), to initiate regeneration, until the message is cleared. Note: The importance of the message and responding to it immediately. Clearing the message will only make the message disappear temporarily and not correct the condition.
If the filter cannot be cleaned and the soot continues to build — reaching a third threshold — the ECM will set the DTC P2463 (DPF Soot Accumulation), placing the vehicle in reduced engine power. Drivers will receive a corresponding DIC message.

Repair Procedure:  At this point, the vehicle will need to be serviced. When DTC P2463 is set, technicians should turn to the Service Information and follow the correlating diagnostic procedure. It may be necessary to replace the filter. If the DTC is not set, refer owners to their owner’s manual or diesel engine supplement for sections titled “Diesel Particulate Filter” to familiarize them with the system.
For more Tech Tips, visit our blog page by clicking here.