July 9, 2026 4:30 PM, EDT
| Updated: July 13, 2026 11:20 AM, EDT
From left: Paccar CEO Preston Feight and American Trucking Associations President Chris Spear listen as EPA Administrator Lee Zeldin discusses the proposed revision. (ATA)
Key Takeaways:
EPA proposed rolling back emissions-system warranty requirements for new heavy-duty trucks, reducing expected cost increases for new equipment next year.The proposal keeps tighter NOx limits set for January while scaling back warranty expansion and delaying updated useful life extensions.The rule would maintain an 80% NOx reduction requirement as the Trump administration seeks to unwind Biden-era vehicle pollution rules.
The Environmental Protection Agency’s proposed revision of its nitrogen oxide-emissions rule would include rolling back warranty requirements for new heavy-duty trucks while softening compliance standards.
EPA laid out the initiatives July 9 as part of a long-awaited notice of proposed rulemaking (NPRM) on changes to nitrogen oxide tailpipe emissions regulations proposed by the Biden administration in late 2022.
In a speech at the America 250 Great American State Fair unveiling the plans, EPA Administrator Lee Zeldin said: “Manufacturers spoke up, suppliers spoke up, fleets, dealers and drivers all spoke up. They warned that the new requirements couldn’t be met in time, that it would drive up costs, that it would force companies to rush products to market before they were ready. In the past, Washington wasn’t listening. However, the Trump EPA is.”
In the headline revision, warranties for heavy-duty truck emissions mitigation equipment will be 100,000 miles or five years rather than 450,000 miles or 10 years under the existing rule.
If the proposed rulemaking survives public hearings and a comment period in its current form, then truck manufacturers will be able to set their prices for model-year 2027 trucks.
The EPA said it expects truck buyers to see up to $6,000 per vehicle in emissions-related warranty savings.
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But some original equipment manufacturers told carriers in May that potential price hikes — estimated at $20,000 — could be cut in half if the 100,000-mile or five-year warranty terms were in place.
When it comes to the actual tailpipe emissions, EPA is set to leave in place a Biden-era requirement that NOx emissions for heavy-duty trucks fall to 35 milligrams per horsepower-hour from 200 mg/hp-hr as expected.
The NPRM, however, will allow truck makers to sell heavy-duty vehicles that do not meet the NOx standard if they pay a fee. That fee will be based on the level of noncompliance.
It also will allow up to 5% of an OEM’s U.S.-directed production to meet pre-2027 requirements between 2027 and 2029 without the use of NOx credits as is currently required. Daimler Truck North America, International Motors and Paccar all build trucks in Mexico as well as in the U.S.
In addition, the NPRM would delay a scheduled increase to regulatory useful life — or the period a vehicle must stay compliant with emissions regulations — by three years and reduce the mileage component. The warranty would become effective in 2030 and would be for 435,000 miles, not 650,000 miles as previously determined.
All the changes follow Zeldin announcing in March 2025 that the 2022 Heavy-Duty Nitrogen Oxides rule would be re-evaluated, citing consumer choice and cost concerns.
The revisions won plaudits from the most senior executives at North America’s truck and engine manufacturers.
“This emissions warranty change … is a really big deal because we’re no longer going to require that everybody buy up front an emissions warranty over the whole life of the product. They have choice. Some choose to do that. That’s a part of their business model. But it gives them the flexibility and choice and from a cost perspective,” Cummins CEO Jennifer Rumsey told Zeldin at the unveiling in Washington. “It’s really going to help them and their businesses.”
Rumsey’s counterpart at Kenworth and Peterbilt parent company Paccar, Preston Feight, concurred: “The actions you’ve taken make a big difference. We hear from our customers all the time about the spec of their trucks, and it feeds into the work you’re doing. They want trucks that can do the job it needs to do most efficiently, most reliably, most durably. So, they’re in line with the EPA in making a better environment because they want fuel-efficient trucks.
Truck and engine manufacturers already have their products — which took multiple years and many thousands of man-hours to develop — out. International Motors was the first to do so, unveiling plans in January for an EPA 2027-compliant S13 engine.
Paccar said in February it would have two engine platforms available. Cummins’ 2027 X15 engine debuted in March. Daimler Truck North America, whose CEO John O’Leary was at the launch, also unveiled its engine lineup in March.
During a press briefing after the NPRM unveiling, O’Leary and Feight said the details contained in the proposal were likely to aid carriers and truck demand.
“The helpfulness is clarity,” said Feight. “And the second part is total cost of ownership for our customers so they can make the choices they need to buy the equipment they need to run their businesses as efficiently as possible. We serve them. This is a great opportunity to work with the government in partnership to allow our customers to be more successful.”
EPA will hold virtual public hearings on the NPRM July 29-30. If there is sufficient interest, an additional day of hearings will be held July 31, the agency said. Comments must be received on or before Aug. 29.
An NPRM is a formal document issued by a federal agency that announces the intent to change, add or remove regulations. It outlines the proposal and invites public comments.
Both American Trucking Associations and the Owner-Operator Independent Drivers Association intend to file comments, and the latter believes the revisions did not go far enough.
ATA President Chris Spear — who also was on the dais with Zeldin for the announcement — said in comments released after the event: “ATA has been clear from day one: New environmental standards must be achievable, affordable and reliable. If a truck cannot perform safely and efficiently on America’s highways, then the freight does not move, shelves do not get stocked and our economy pays the price.”