Navistar filed a lawsuit on July 5 against the Environmental Protection Agency (EPA), alleging that the Agency allows competitors to circumvent 2010 Emissions Regulations.

According to the case file (attached), Navistar alleges that "For MY 2010 and MY 2011, EPA certified (and intends to continue certifying) SCR-equipped engines that are programmed to run for length periods without DEF, with the wrong fluid (e.g. water), with frozen fluid, or with the SCR system disconnected (and thus, with zero SCR-control of NOx emissions during those disabled conditions)..." among other allegations.

In other words, Navistar is alleging that drivers could defeat the emissions standards by theoretically forgetting or refusing to fill the DEF reservoir, or substituting it with something cheaper, even water. The suit, filed in the U.S. District Court for the District of Columbia, alleges that the EPA certified SCR systems without taking those factors into account.

In gauging fleet manager reactions, one fleet manager, who wished to remain anonymous said, "I do believe it is sour grapes on Navistar's part since they are the only ones without SCR and are trying to make a point." 

In June, the EPA announced a proposal that would increase safeguards to ensure drivers fill or replenish DEF tanks. The proposal also calls for better warning systems to identify and respond to low levels or poor-quality DEF and increase tamper resistance.

Another fleet manager, who wished to remain anonymous stated, "While Navistar's allegations could possibly occur, running without proper DEF (32-percent urea/68-percent deionized water) would not last for long. Within an hour, the engine would begin to derate in terms of horsepower and road speed, roughly 20 percent, 50 percent, and 80 percent incrementally, and then the engine would die within a very short time," he said. "Now, the truck has to be towed to a repair facility, failure codes cleared, DPF inspected and/or replaced, DPF added and a hefty bill paid. That is what actually happens, and believe it or not that's the good part."

According to the fleet manager, "The reason it is good is that the system is trying to protect the DPF from permanent damage and carbon plugging. If this scenario is repeated for whatever reason the DPF can easily be damaged to the point where it can't be serviced or cleaned and most likely, the DPF substrate will crack. If, and when, this occurs, the DPF filter has to be replaced at a cost typically between $3,000-$6,000, depending on the engine make and application. Whether the driver is an employee or an owner operator, he will not risk his load, his money or his continued livelihood more than once."

What do you think? Do you agree that it's just "sour grapes" on Navistar's part, or that running without DEF won't last for long and that drivers/operators won't risk their loads? Let me know! 

Lauren Fletcher

Lauren Fletcher

Executive Editor

Lauren Fletcher has covered the truck fleet industry since 2006 and is the executive editor of Work Truck magazine. With a particular focus on educational, tips and trends pieces in the vocational truck industry, check out her Truck Chat video series or Chatty Chassis blog for more!