Light & Medium Truck | Navistar Says SCR Systems Can Be Defeated
Navistar Says SCR Systems Can Be Defeated
By Light Medium Truck
Navistar Inc. recently attacked competitors’ 2010 selective catalytic control engines on two fronts, telling environmental regulators that pollution controls on the engines could be easily defeated, and telling fleet managers that every gallon of diesel fuel an SCR engine saves will come at the cost of at least that much diesel exhaust fluid consumed.
At a joint state-federal workshop in California this month, truck and engine maker Navistar presented a 15-minute video that purported to show drivers of SCR-equipped trucks flouting 2010 emissions regulations by operating heavy- and medium-duty SCR trucks for thousands of miles using water instead of diesel exhaust fluid.
Engines with SCR are intended to “de-rate,” or lose power, if their tanks holding the urea-water solution known as DEF are empty. Navistar said that substituting plain water for DEF tricked the tank’s sensors.
“Truck owners are paying a substantial price to comply with 2010 NOx requirements. They and the public deserve to know that the new equipment they are purchasing actually works as promised,” said Jack Allen, president of Navistar’s North American truck group.
Volvo Group and Cummins Inc., both of which sell SCR engines, participated in the July 20 workshop and said their trucks and engines, which have passed 2010 federal and California emission certification, function properly.
In response to the video, Daimler Trucks North America stated its “emissions systems operate as designed, meeting federal and state air-quality standards that reduce particulate matter and nitrogen oxides to near-zero levels without the use of credits.