DPF Maintenance on heavy duty trucks

DPF Maintenance: What It Is & Why It’s Important

Spring has certainly sprung, which means that it’s the perfect time for spring cleaning, and to ensure that your truck fleet is ready for the spring and summer months. Not only is it a good time of year for a wash down of your trucks, it’s also the ideal time for general maintenance and servicing. 

One of the most important parts that needs to be regularly maintained is your diesel particulate filter (DPF). Though servicing this part of your truck may be easily forgotten, regular maintenance of this filter can save you a headache and hours of downtime in the long run.


What Is A DPF?

The diesel particulate filter was first introduced back in 2007 as a way to reduce the particles emitted from diesel exhaust. These particles can be harmful to people’s health, as well as having the potential to cause environmental damage. 

A DPF works by trapping these soot particles from the exhaust. Where a catalytic converter is designed to reduce the gas emissions of a car, a DPF traps the solid particles, including tiny nanoparticles, until they can be burnt off. So, in basic terms, a DPF is essentially a ‘soot catcher’. Once it catches the particles it will then burn this soot off at a high temperature through active or passive regeneration.

There are many different designs of DPF’s, with ceramic honeycomb filters being some of the most common. This forces the exhaust to flow through the walls of the filter with the soot getting trapped via depth filtration inside the pores of the filter, as well as on the surface of the walls. Ceramic is a popular choice due to its durability under high temperatures.


What Is Active Regeneration?

Active regeneration is when the DPF calculates the amount of soot and ash, then, using heat generated from the exhaust along with an injection of fuel, burning the soot and ash off. This can happen at any time the truck is on.


What Is Passive Regeneration?

Passive regeneration works in exactly the same way as active regeneration with one major difference: it doesn’t happen automatically. Instead, a warning light on the dash will indicate that regeneration needs to happen, and it needs to be manually switched on while the truck is parked.


De-Ashing & DPF Cleaning Methods

DPF Maintenance services in MN

If the DPF gets rid of soot build-up regularly, then why is DPF maintenance needed at all? Well, soot isn’t the only thing that builds up. Ash is a byproduct of oil and can’t be burned away. As it builds up, it blocks the filters, meaning that you will start to get warning lights for regen more regularly, and it will decrease the efficiency of your DPF. 

It’s very important that this is professionally cleaned as the ash is classed as hazardous waste and must be handled in a safe manner. Professional DPF maintenance can also include valuable DPF system testing in order to know that each component is working correctly.


Bake & Blow

This method uses high-pressure air to loosen the built-up ash that has accumulated. Sometimes, this is all that is needed to clean the filter, and DPF testing will occur to see if there are any remaining flow restrictions. If there is, the DPF will undergo high temperature in order to loosen the material before it is blown away.


Liquid Wash

A liquid wash is when the DPF is soaked in cleaning fluid to remove the sintered ash deposits. When this is happening, a replacement DPF is usually fitted in the truck so it doesn’t have to wait.


Aqueous Clean

This is seen as a more eco-friendly way to clean a filter since it doesn’t require baking or cleaning solutions, only water. While a pressure washer isn’t recommended when cleaning a DPF due to the damage it can cause, an aqueous system uses low-pressure but high-volume water to get the job done in a matter of hours.

Since the DPF is a major part of all heavy-duty tractor-trailer rigs, regular maintenance always needs to be a top priority. It is critical that the system is working properly and is kept in good condition.


DPF Maintenance: When to Clean

North American Fleet ServicesIt’s important to schedule DPF testing before you think it needs to be done. By the time a warning light turns on, your filter might need some serious de-ashing, and could even be damaged. By developing a proper maintenance schedule, you can keep your truck running smoothly and avoid DPF issues. Other issues such as internal engine oil or coolant leaks can cause serious damage, and this might mean replacing the filter.

If you need to complete DPF maintenance for your fleet, contact North American Trailer for all of your service needs. Our team has over 35 years in the trucking maintenance business and we service fleets in locations all around Minnesota and North Dakota. Contact us today for more information!

Inver Grove Heights, MN


11015 Clark Rd
Inver Grove Heights, MN 55077

Clearwater, MN


750 Heaton BLVD
Clearwater, MN 55320
CT # 14992

Stanley, ND


8116 61st St. NW
Stanley, ND 58784
CT# 12768

Scanlon, MN


1325 Hwy 45
Scanlon, MN 55720
CT# 11774

Chippewa Falls, WI


4306 123rd Street
Chippewa Falls, WI 54729
CT # 15568