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What is a diesel particulate filter or DPF filter and how it works

A diesel particulate filter, or DPF, is an exhaust aftertreatment device that traps particulate matter such as soot and ash. A DPF typically uses a substrate made of a ceramic material that is formed into a honeycomb structure.

Oftentimes, blocked diesel particulate filters are caused by short journeys at low speeds. Vehicles operating at low speeds on short journeys are unable to meet the requirements for the filter to clean itself.

The lifespan of a diesel particulate filter varies based on the application. DPFs may fail sooner if they are not well maintained. Additionally, filter blockage can be caused using the wrong type of oil, performance modifications, using low-quality fuel or even running the car frequently on a low fuel level.

DPF filter is designed to conduct exhaust fumes out of the trucks engine, so when it is blocked, these fumes cannot leave the engine as quickly. This stops the engine from working to its full capacity and will invariably reduce your fuel efficiency.

Finding out if your filter is blocked: Usually, when the filter becomes clogged or an error occurs in the system, an orange light will appear on your dashboard. When this alert lights up, you know your filter is most likely blocked, and a regeneration may be required.

Just like there are two main particulates being filtered, there are two types of cleanings that are required. Regeneration cleans out the soot by converting carbon-to-carbon dioxide, and the ash is removed by removing the filter and cleaning it in a machine with compressed air.

The best way to maintain a DPF is to make sure it’s fully able to regenerate itself when it’s full of soot (when the warning light appears). There are two types of regeneration: passive and active.

It’s no secret that as trucks age, their value decreases. It’s much easier to clean a diesel particulate filter than it is to replace it, which is why understanding how these filters work and performing regular maintenance is so important.

Replacing a diesel particulate filter can be expensive. A new filter can cost anywhere from $3,000 to $10,000. As official dealers for Isuzu Trucks, Hino Trucks, Volvo Trucks, Mitsubishi Fuso Trucks, and Cummins engines, we can offer the most competitive pricing on the next DPF filter replacement for your commercial vehicle.

If a parts supplier charges less for a DPF, be wary—the filter must be the correct type for your vehicle. Otherwise, you will most likely end up spending more on repairs. Contact TruckMax service department for your next DPF service.


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