Dive Brief:
- The Truck and Engine Manufacturers Association is urging the Environmental Protection Agency to strengthen and finalize proposed amendments to its model year 2027 heavy-duty nitrogen oxide rule, according to a Aug. 28 press release.
- In 59-pages of comments, the industry group said it appreciates the agency’s work to limit derate impacts on truck and equipment operators, but the association wants final requirements that are technologically sound, cost-effective and workable in the real world.
- “This rulemaking is an opportunity to preserve the emission reductions achieved through proven technologies while correcting requirements that can impose unnecessary costs and operational burdens,” said EMA President and CEO Jacqueline Gelb in the release. “The final rule must provide manufacturers with the clarity and certainty they need to deliver reliable, affordable equipment to their customers.”
Dive Insight:
The EMA filed its comments four months before the new standards take effect — timing that drives the first of its five recommendations: Finalize the amendments before the end of 2026, giving manufacturers time to refine model year 2027 products.
The remaining four ask the EPA to:
- Keep current emissions warranty periods in place indefinitely and delay useful life requirements
- Revise selective catalytic reduction and diesel exhaust fluid requirements
- Formalize the agency’s August 2025 inducement guidance for nonroad engines
- Alter testing and compliance procedures to account for cold-weather operations, engine warmup, emission-system regeneration and other conditions that can skew results
The Owner-Operator Independent Drivers Association raised many of the same concerns, but the two groups split when it came to the support of the audible and visual alerts that would replace derates for SCR- and DEF-related inducements.
The OOIDA backs the approach, arguing that engine control systems should warn drivers directly.
“An audible warning system would allow drivers to properly address DEF problems in a safe manner without having to drastically reduce speeds, miss deliveries, or be sidelined for days/weeks at a time,” the group wrote in its submitted comments.
The association advised the EPA to shorten the initial alert to 30 seconds, rather than the proposed 90 seconds, and laid out a tiered cadence for DEF-level warnings that escalates from 30 seconds to 90 seconds as the tank empties.
EMA said the EPA should stick with its existing guidance, claiming the proposed audible alerts are not well-suited for nonroad machinery or for retrofits given the hardware complexity and the software upgrades involved.
“Audible and visual alerts in a commercial vehicle must be carefully designed to deliver the necessary message to the driver, but without confusing or distracting them,” EMA wrote in its comments. “Successful human factors engineering takes time, usually by testing designs with actual drivers in real-world operating environments. That iterative process of designing, testing, and redesigning can take multiple years to complete properly.”
The comment period closed Aug. 29. The EPA is expected to issue a final rule before the end of the year.
