DEF Changes Are One Less Hurdle to Efficiency
April 14, 2026
With the EPA’s recent removal of Diesel Exhaust Fluid or DEF sensor requirements and the accompanying loss of speed and shutdowns due to sensor malfunctions, the motor carriers around the nation are relieved to have one less hurdle to productivity.
Greg Fulton, president of the Colorado Motor Carriers Association, said the DEF sensor change from Urea Quality Sensors to nitrous oxide sensors won’t address the high prices, but will remedy the problems that come with a faulty DEF sensor and his industry welcomes the changes.
Diesel Exhaust Fluid or DEF sensor failures, according to the U.S. Small Business Association, cost American farmers about $4 billion annually.
According to a release by the EPA, under new Diesel Exhaust Fluid sensor requirements, the approved nitrous oxide sensor-based software updates can be installed on existing engines without being treated as illegal tampering under the Clean Air Act.
This is in line with EPA’s February 2026 Right to Repair clarification guidance, which removed a major barrier keeping farmers from fixing their faulty DEF systems in the field. EPA anticipates the switch will greatly curb errors that traditional sensor technologies have been prone to and reduce the issues Americans face with inaccurate DEF failures. According to the U.S. Small Business Administration (SBA), this guidance will save farmers $4.4 billion a year and this action will provide $13.79 billion a year of savings to Americans.
Fulton said while the DEF systems won’t go away, the frustration of the sensors that frequently fail despite the engine functioning correctly, could.
He said his industry is hopeful for solutions that are workable, as opposed to, for example, requiring electric trucks that would place an impossible load on the electric grid to power overnight. Fulton said he is also hopeful attention will turn from electric trucks to fleets that run on renewable natural gas.
“I will say, the changes the EPA is making, we welcome those,” he said. “We welcome that the administration rolled back this thing where they had the advanced clean truck, which would have required is to buy so many or the dealerships, really, to sell so many zero emission vehicles. Even though electric vehicles are coming along, on the heavy-duty side, they’re a real challenge because of their weight, their range, the charging infrastructure and everything else that goes along with that.”
Renewable natural gas from recovered methane is of interest to his industry as well as a product that make sense in the industry and have the potential to also help local economies.
He said there are a couple thousand trucks operating on RNG in the state currently, primarily in the waste disposal business and its use can also be an economic boon to rural areas.
There is great interest in renewable diesel, he said, and there is a processing facility in Cheyenne, but they sell to California and buyers there, through tax credits, price others out of the market.
Fulton said that trucking, like agriculture, is drowning in government regulations. So much so, in fact, that one of the jobs in trucking with the highest rate of growth is currently compliance specialists.
