EL MONTE, Cal. — Representatives from Volvo Group attended a recent workshop with environmental regulators, initiated by Navistar to raise concerns about selective catalytic reduction (SCR).

The company strongly defended the effectiveness of SCR and warned against revamping the regulations with the roll-out of EPA2010-compliant engines already well underway.

“We question the need to make modifications to SCR strategies just six months after SCR products were brought to market,” said Steve Berry, director of government relations with Volvo Powertrain. “These strategies were thoughtfully developed in good faith by EPA, CARB and EMA, applying their collective best judgment to balance SCR operation with other critical issues, not the least of which is safety.”

Volvo raised the point that unjustifiably limiting engine torque excessively could cause safety concerns on the road or strand drivers in the middle of nowhere in adverse conditions.

Berry went on to say “We have seen no evidence of DEF refill or SCR tampering issues in the field and believe it is premature to impose new restrictions in the absence of any evidence of need.”

John Mies, vice-president, corporate communications with Mack and Volvo called out Navistar.

“The fact is that a Mack or Volvo truck running at 0.2 grams (per brake hp/hr NOx) is and will continue to be much better for the environment than a Navistar truck running at 0.5 grams – and no amount of changes to the inducement strategies will change that,” he said. “Let’s make sure that what we do is truly in the interest of the environment and the public. And let’s not penalize those who have worked with you in good faith, and reward those who are trying to manipulate the system for their own competitive advantage.”

Volvo Group has already delivered more than 3,500 Volvo and Mack engines with SCR in North America and has received orders for more than 10,000.

The workshop was held July 20 at the request of Navistar, which is the only heavy-duty truck and engine manufacturer in North America to pursue EPA2010 compliance without using SCR. Navistar contends that in certain situations, SCR-equipped engines can exceed EPA NOx limits.