New Diesel Owner? What Should You Know About The Particulate Filter?

Posted on: 6 August 2015

If you've recently purchased your first diesel car or truck, you're not alone -- sales of diesel vehicles have increased significantly over the last couple of years, in part due to the improved efficiency and wider variety of available fuel sources for these vehicles. While diesels can look and function in ways that often make them indistinguishable from gasoline vehicles, there are some key maintenance and repair differences you'll need to be aware of before your first servicing appointment. Read on to learn more info about the diesel particulate filter and how its proper maintenance can keep your vehicle in good running for hundreds of thousands of miles.

What is the diesel particulate filter?

When diesel fuel is used to power an engine, soot and other particulates are created and vented through the exhaust. (These particulates can sometimes be seen in the form of a thick, black cloud following the takeoff of a diesel vehicle with an inoperable or missing exhaust). In an effort to improve air quality and reduce pollution caused by auto exhaust, the federal government has implemented a number of standards for auto manufacturers to help reduce harmful engine emissions. The DPF is one of these innovations, and helps filter out nearly all polluting particles produced by your engine -- anywhere from 85 to 100 percent.

Should you have your DPF cleaned or replaced?

As you rack up miles on your diesel engine, your DPF will eventually become full of ash and other particles filtered out of your exhaust. This usually happens at around the 100,000 or 150,000 mile mark. At this time, you may notice your engine becoming less efficient -- it might seem sluggish during acceleration, or your average fuel economy could drop dramatically. In extreme cases, your engine could completely lose power, causing a crash. It's important to restore your DPF to a new or like-new state to help prevent damage to your engine (or your wallet). Although one way to quickly restore efficiency is simply to remove your DPF, as your vehicle can operate without it, doing so can put you in violation of state and federal emissions laws and subject you to heavy civil penalties.

This means you'll need to make an appointment with an auto service shop to go through your options, including cleaning and replacement.

Cleaning your DPF is easier than it might seem. The particulates that collect in this filter are the product at combustion at a certain heat level. Because your diesel engine doesn't get hot enough to fully incinerate the fuel, some soot and other byproducts remain. By heating the DPF up to ultra-high levels, these particulates are essentially vaporized into a fine ash that can be cleaned from the inside of the filter. This is a quick process and can usually be performed in conjunction with an oil change or other regular maintenance. You'll likely find yourself paying anywhere from $300 to $500 or more to clean your DPF, a relative bargain when considering the infrequent maintenance schedule.

Your other option is replacement. By replacing your DPF, you'll be guaranteed another 100,000 to 150,000 miles of smooth performance with minimal maintenance -- however, you'll also be paying for this privilege. A new DPF can cost anywhere from $1,000 to $1,700, including labor costs associated with installation. Your final decision may depend on how much longer you're planning to keep your vehicle. If you're hoping to sell or trade in soon, a cleaning may buy you the time you need; while if you'd like to drive it until it can no longer be repaired, you should more than get your money's worth from a brand new DPF