ORLANDO, Fla. –Officials with Detroit Diesel have openly attacked critics of SCR technology -and the use of Diesel Exhaust Fluid to treat vehicle exhaust -suggesting that the claims are little more than “myths.”

Presentations made here during the spring meeting of the Technology and Maintenance Council were hardly a veiled attack on Navistar, which is insisting that the next round of emission standards should be met by refining the combustion process.

While claims have been circulating that the new Diesel Exhaust Fluid becomes toxic at temperatures above 118 Fahrenheit, Detroit Diesel countered that this argument was “extremely exaggerated,” and quoted a report by James Spooner of the Colonial Chemical Company to prove its point.

“Urea is a non-hazardous material that does not become toxic at any temperature,” he said.

Claims of steep prices for the fluid were also countered.

“We can’t predict what prices will be for DEF or even diesel fuel,” admitted Mark Lampert, senior vice-president, sales for Daimler Trucks North America. “(But) DEF prices will not be the problem that one competitor will have you believe.”

He also questioned claims that SCR forces fleets to bear the cost of compliance when it comes to the new emission standards. New in-cylinder technology and the higher fuel consumption that comes with it will also carry a cost, he said.

Detroit Diesel also made a point of stressing that it will meet the coming emission standards with “no credits, no compromises,”in an obvious attack on manufacturers that will need to rely on so-called “emission credits” for specific engines that do not meet the standards as of January.

“While sanctioned by the EPA as a bridging step toward 2010 compliance, they actually result in unnecessary levels of higher emissions during the interim -especially when more desirable near-zero emissions levels can be achieved with the use of SCR technology,” said Lampert.

Worries that the new fluid will freeze at 11 Fahrenheit were also countered with the fact that the tanks will be warmed by immersion heaters, while the EPA will allow a truck to operate while the Diesel Exhaust Fluid is thawing. Questions about whether the fluid was flammable were discounted, along with a note that it only tended to evaporate when stored in desert conditions beyond its 18-month shelf life.

The company also seemed to stress the growing importance of options that integrate truck and engine together.

“Ten years ago, the choice of engines was wide open. Integration with the chassis was not complex, you could get any engine with virtually any truck, there was much less vertical integration across the industry,”said Dr. Elmar Boeckenhoff, senior vice-president, engineering and technology. •