Daimler, Navistar Escalate Feud Over Rival 2010 Engine Systems

This story appears in the Aug. 16 print edition of Transport Topics.

Daimler Trucks North America revved up the dispute between proponents of the two different diesel emissions reduction technologies, saying in a widely distributed letter to the trucking industry that rival Navistar Inc. “intentionally confused customers with fear-mongering, deception and distraction.”

The letter, published Aug. 9 as an advertisement in Transport Topics and later disseminated as a mass e-mail, claimed that when Navistar engaged a consultant to test SCR technology, it was in effect “hiring a third party to break the law” by deliberately defeating competitors’ emissions controls when it used plain water rather than the required urea solution.

DTNA and all other major diesel engine makers except Navistar use selective catalytic reduction to meet the U.S. Environmental Protection Agency’s 2010 rules. Navistar’s 2010 International trucks use only exhaust gas recirculation.

SCR requires a urea-water solution called diesel exhaust fluid, which is injected into the exhaust system, enabling a catalytic converter to remove nitrogen oxides. EGR requires no additional fluids.

Navistar fired back after DTNA’s advertisement appeared, with statements that it had been “shocked” when the research firm was able to run SCR engines with only plain water in the DEF tanks.

The consultant Navistar hired produced a video that the manufacturer presented to an emissions workshop in July and later distributed widely (7-26, p. 1).

“With more than a decade to prepare to meet 2010 emissions standards, all but one heavy-duty trucking manufacturer invested the necessary time, money and brainpower to develop the best technology possible to meet stringent new requirements,” Daimler wrote in its letter .

“Though we’re all competitors, the rest of us understood the importance of the larger cause,” Daimler said.

“Instead, Navistar has chosen to do the exact opposite. They’ve painted a picture of our industry, our customers and their operators as a group that will intentionally break the law and circumvent the EPA’s emission control regulations,” DTNA said in the letter.

The letter said it was Navistar, not SCR proponents, that broke the law by hiring a company to run tests on 2010 SCR trucks “out of EPA compliance.”

Daimler also said it has not seen any evidence that Navistar actually has developed a 2010-compliant EGR engine.

DTNA builds Freightliner and Western Star trucks, as well as Detroit Diesel engines.

EPA had no immediate comment on the claims of either company.

Jack Allen, president of Navi-star’s North American truck group, said that the result of tests on SCR trucks by an “objective outside agency” on SCR trucks “was indeed shocking.”

Navistar hired Ensight LLC, Walnut Creek, Calif., which describes itself on its website as an environmental consulting company.

“All of the [test] units could actually run on water with no liquid urea, which, of course, causes emissions levels to go through the roof,” Allen said in a written statement Aug. 11. “This invalidates the fundamental basics of the SCR system and places an unfair responsibility on the customer, rather than the manufacturer.”

Allen brushed aside DTNA’s contention that the tests were illegal, saying that Navistar “acquired a testing exemption contained in the Clean Air Act.”

He said the testing proved that the SCR system “does not begin using liquid urea until it reaches 450 degrees Fahrenheit. In stop-and-go traffic and most urban areas, the system does not often reach those temperatures, so the use of liquid urea would never be triggered.”

Allen said the test also proved that an SCR truck could run “thousands of miles with no liquid urea in the tank per EPA guidelines. And if you added a small amount of liquid urea to the tank, once that was used up, you could travel thousands more miles.”

EPA requires that truck and engine producers install sensors to detect when the DEF tank on an SCR truck is empty, signaling the engine to lose power.

But Navistar’s video showed people filling DEF tanks with what they said was tap water and then driving the trucks without any apparent problems.

The testing company ran one truck for 1,200 miles with only water in the DEF tank, Navistar spokesman Roy Wiley told TT.

Volvo Trucks North America spokesman John Mies said that simply substituting water for DEF would not allow a Volvo truck to operate normally.

“No, a driver could not fill a Volvo DEF tank with water and run the truck without any problems,” Mies told TT. “Inappropriate DEF would be detected by a NOx sensor. If the driver didn’t replace the DEF, the engine would first derate and ultimately be limited to 5 miles per hour, if the driver refilled the diesel fuel and neglected to address the DEF issue.”

Spokesmen from VTNA’s sister company Mack Trucks, DTNA and independent engine maker Cummins made similar statements to TT. Paccar Inc., parent company of Peterbilt Motors Co. and Kenworth Truck Co., de-clined to comment.

Navistar said only one of the four SCR trucks in its test lost power, and then to only 55 mph. The others ran without trouble, and none set off alarms with DEF tanks filled with water, Wiley said.

EPA declined to discuss any of the specific contentions of any company.

“The agency is reviewing all of the information presented at the [July 20] workshop and will follow up on any compliance issues identified,” EPA spokeswoman Enesta Jones told TT.