What the Diesel Particle Filter or DPF Is

New diesel pickups and passenger cars, as well as some commercial vehicles, built after 2007 must be shipped with a DPF or diesel particulate filter installed in the exhaust system.

What It Does

The diesel particle filter removes polluting chemical that result from diesel combustion before these particles of polluting matter reach the tailpipe and enter the atmosphere. It works similar to a catalytic converter by trapping and re-heating pollution.

Some remains behind, hence the name "filter" and not catalytic converter.

Eventually all DPF filters will clog up at some time. Most manufacturers will swear this will be a long time, but since the technology is so new we will only find out through time how long they last. They are not cheap to replace and this has a lot of diesel aficionados worried.

The Affect of Diesel Particle Filters or DPF on Fuel Mileage

The diesel particle filter itself creates an obstruction in the exhaust system. Combine this with the diesel catalytic converter and you have created several pounds per square inch of blockage on your exhaust pipe.

Since adding the DPF to the exhaust system does result in a loss of fuel mileage, many wonder why the government made this technology a requirement when it is not even used in most parts of the world. Now that diesel sold in the U.S. is all ultra low sulphur there is not as much pollutant matter given off by diesel engines.

Is It Legal To Remove Your DPF?

No. Let me make that quite clear. For highway use you cannot remove the diesel particle filter. Yet for off road use it is perfectly legal to do so. Examples of off road use include farm vehicles that do not travel on the highway and diesel four wheel drive vehicles used on trails an off road exclusively.

If you choose to remove your DPF for off road use you will cause a problem with your vehicle's computer system.

Since the DPF has sensors that are attached to your computer, the computer will always be looking for it, and sending a message to recirculate exhaust gasses through the DPF.

This problem can be overcome using a diesel programmer such as the Quadzilla. These programmers have a feature that you can download from the manufacturer's website to "delete the DPF".

Once you download this feature to the programmer you must check a disclaimer box stating that the vehicle will be used for off road use only.

Summary

Remove your DPF only at your own risk and if you plan to use the vehicle off road only since tampering with it is against federal law and can result in a fine of up to several thousand dollars.