Why is a Diesel Particulate Filter (DPF) on my truck? What is a Diesel Particulate Filter (DPF)?
DPFs, or Diesel Particulate Filters, are required to reduce exhaust emissions on virtually all diesel engines. Whether you have an over-the-road truck or industrial equipment, you likely have a DPF attached to the exhaust system. Diesel engines emit pollutants and to reduce the amount of these pollutants diesel engines have been fitted with a filter in the exhaust pipe to capture soot particles.
The materials in a DPF traps the particulates (black smoke / soot) flowing out the exhaust pipe. The filter element has reached the end of its life when holes or cracks appear that allow unfiltered exhaust to flow downstream. During its lifetime, the DPF are typically removed and cleaned 2-3 times. The range of DPF service intervals is between 80,000 miles to 250,000 miles depending on operating conditions. Typical long haul heavy duty diesel truck travels more than 80,000 miles per year so depending on the severity of the duty cycle, off-truck cleaning of the DPF could take place between once a year and once every three years.
Diesel Particulate Filters capture soot until they fill up and create too much backpressure.
Diesel Particulate Filter Cleaning and Regeneration / Re-Gen are not the same thing.
Active or Passive.
The DPF technology currently available utilizes what’s called a wall-flow filter that’s positioned in the exhaust system.
The process of combusting these trapped particulates inside the filter without an intolerable buildup of engine backpressure is called filter regeneration. If you think of this as a self-cleaning you're only half right.
Starting in 2007, the US Environmental Protection Agency (EPA) made DPFs mandatory for highway diesels to achieve the low soot emissions limits.