When diesel engines operate they product both soot and ash. Soot develops in the exhaust, and ash comes from the burning of motor oil. The longer the motor runs, the more it internally burns off the soot, but the ash itself is typically trapped in a special filter known as the diesel particulate filter.
This filter is like a honeycomb. It heats up and allows the ash to burn off, but when the truck is constantly starting and stopping, as in city traffic, or if it is idling for long periods the ash can build up in the filter. This is why regular diesel particulate filter cleaning is important.
Don’t Ignore the Warnings
Although the process of regeneration, or the burning of the soot, will happen when the truck is in use, it can also be initiated by the driver. When warning systems on the dash indicate the filter needs to be regenerated, it can be completed by the driver on the road.
However, this doesn’t remove all the ash in the filter. At least one a year the truck should be brought in for a complete diesel particulate filter cleaning service. This will allow the technicians to actually remove that residual ash through a specialized process.
This process will include air used to blow out the ash from the filter. Additionally, at this time, the filter will be completely tested and the results recorded. If the filter is not completely cleaned using air, it can also be cleaned using a thermal process that creates the optimal conditions to burn out the harmful ash.
After this process is complete the filter is thoroughly washed, dried and inspected, and then it is ready to be replaced and reused.
Protecting Your Filter
Typically it is recommended to complete a diesel particulate filter cleaning every 50,000 miles, particularly if the majority of those miles are city driving or stop and go driving.
With routine cleaning the filter itself is protected and about 95% of all filters will be cleaned and can be used again. Old filters or filters with defects or excessive residue may not be suitable for reuse, and a replacement filter will be required in this case.
Typically the entire process of a filter cleaning takes about an hour. It can be completed at most truck repair centers, or it can be completed as part of a routine inspection and maintenance check for the whole vehicle.