EL MONTE, Cal. — Navistar has formally voiced concerns over “compliance loopholes” that it says may be exploited by truck and engine manufacturers using selective catalytic reduction (SCR).
Navistar, which is the only North American truck and engine maker to avoid SCR, has complained to the EPA and CARB that regulatory loopholes allow engines with SCR to operate without diesel exhaust fluid in certain situations, potentially exceeding stringent NOx limits. The manufacturer first launched a lawsuit against the environmental groups and then later dropped the suit when the groups agreed to work with Navistar to reach an acceptable solution through joint workshops.
“Navistar first identified these loopholes to the agencies and also presented our concerns at today’s workshop,” said Jack Allen, president of Navistar’s North American truck group. “We will be working with the EPA and CARB to ensure full environmental compliance.”
During the recent workshop, Navistar expressed concern that engines using SCR can increase NOx emissions tenfold when urea is not present. It presented research conducted by EnSIGHT as evidence.
One truck tested by EnSIGHT appeared to operate indefinitely with water in place of diesel exhaust fluid, Navistar pointed out. It claims the truck ran 13,000 miles with essentially no NOx control.
Citing European research, Navistar also complained that even when DEF is present, a truck in stop-and-go traffic may not generate high enough exhaust temperatures for the SCR system to function properly, again emitting higher than acceptable levels of NOx.
“Truck owners are paying a substantial price to comply with 2010 NOx requirements,” said Allen. “They, and the public, deserve to know that the new equipment they are purchasing actually works as promised to curb pollution. It’s obvious, however, that these trucks can operate effectively without liquid urea, and that under these and other conditions, SCR NOx emission control is turned off. We’re calling on the EPA and CARB to assure that all vehicles, not just ours, work when they are supposed to be working.”
Truck News is Canada's leading trucking newspaper - news and information for trucking companies, owner/operators, truck drivers and logistics professionals working in the Canadian trucking industry. All posts by Truck News