Mack and Volvo launched large scale programs to remanufacture diesel particulate filters for the trucking industry, which will operate out of the Middletown Remanufacturing Center in Middletown, Pa.

Diesel particulate filters use ceramic filter elements to trap and contain particulate matter in engine exhaust. The particulates are reduced to a fine ash which must be periodically cleaned from the filter element, usually every few hundred thousand miles in normal operation. Trucks sold in 2007 with EPA2007 engines are now approaching the mileage at which filters require routine service. If the filters are not remanufactured, the accumulation over time of ash and other material leads to decreased engine performance.

The program enables Mack and Volvo customers to exchange the used ceramic filter element from their DPF for a clean one when service is required.

The DPFs are remanufactured to more than 90 percent of their original capacity. The remanufacturing process begins by blowing air across the filter element and removing ash and contaminants via a powerful vacuum. Filters with a high level of oil or particulate buildup are baked industrial ovens to further reduce ash and contaminants. According to Bob MacPherson, MRC's manager of lean systems and new engine projects, the power of the program is in the ability to remanufacture in bulk, instead of servicing one filter at a time.

Testing showed the system is capable of removing more ash in one cleaning than other methods could in several cleanings. It can also clean and remove ash from a fully plugged DPF. The system is able to detect cracked filter elements during the cleaning process. And the filter element is not subjected to high-pressure pulses that add additional stress, as with some other techniques.