The latest Cummins EPA27 lobbying file has arrived, although “latest” is doing some exhausting work. Twenty-four environmental, public-health, labour and faith organisations have asked PACCAR, Cummins and Daimler Truck to stop supporting weaker implementation of America’s 2027 heavy-duty NOx rules.
TCAP would like to register its shock.
Unfortunately, the machine appears to be fucking empty.
Life is tougher, after all, when you have to comply without a defeat device.
On 20 July 2026, the coalition wrote directly to PACCAR CEO Preston Feight, Daimler Truck North America CEO John O’Leary and Cummins Chair and CEO Jennifer Rumsey. Its accusation was simple: all three companies had reassured investors that they could meet the 2027 requirements. Nevertheless, when the political kitchen opened a deregulation window, the same executives appeared ready to order from the escape-hatch menu.
Naturally, Cummins brought its clean-technology halo to the table.
This is the company that developed an EPA27 aftertreatment system, advertised the reliability of its 2027 X15 and said its products would be ready for launch. Yet Cummins also stood beside the EPA Administrator while he announced weaker warranty obligations, delayed useful-life requirements and penalties that could let non-compliant engines remain on sale.
Apparently, Cummins was ready for cleaner engines.
It just was not ready to stand behind the fucking things for as long.#
Three Manufacturers Walk Into A State Fair
The setting deserves appreciation.
On 9 July, EPA Administrator Lee Zeldin unveiled the proposal at the Great American State Fair on the National Mall. Behind him sat two heavy-duty trucks. Beside him sat Rumsey, Feight, O’Leary and American Trucking Associations CEO Chris Spear.
Nothing says sober environmental rulemaking like a patriotic fairground panel arranged between the corporate livestock and the deregulation Ferris wheel.
First, Zeldin said manufacturers, suppliers, fleets, dealers and drivers had warned that the requirements could not be met in time. According to the EPA, the proposed revisions could save truck purchasers as much as $6,000 per vehicle and $12 billion overall.
However, the coalition letter points to a small problem with the industry’s crisis narrative.
PACCAR had already told investors it was prepared for the 35-milligram NOx standard and “ready to go with it.” Cummins had said it would be ready to launch products under the 2027 regulations. Meanwhile, Daimler had confirmed that it had developed an engine capable of meeting the standard.
Prepared. Ready. Already fucking there.
Then the regulator offered relief, and the choir changed key before the bunting came down.
Yet the companies did not arrive as baffled village mechanics who had discovered NOx the previous Tuesday. These were vast manufacturers with years of engineering work, regulatory notice, global experience and public claims of preparedness behind them.
Even so, the fairground message became caution, validation, affordability and flexibility.
Indeed, corporate English remains the only language in which “we built it” and “please weaken the rules around it” can occupy the same sentence without security being called.
The Standard Stays – The Spine Gets Sanded Down
Crucially, the EPA proposal does not simply erase the 2027 tailpipe limit. That distinction matters.
Its underlying NOx standard remains in place. However, the surrounding compliance structure would change substantially. The proposal would scale back mandatory emissions warranties, delay longer useful-life requirements, revise testing rules, create nonconformance penalties for certain engines that miss the standard and remove DEF-related derates in favour of warnings.
In other words, the number survives while several of the mechanisms designed to make that number mean something in the real world head into the workshop with a grinder.
Under the 2023 framework, heavy-heavy-duty emissions warranties were due to rise from five years or 100,000 miles to much longer coverage reaching 450,000 miles. The regulatory useful life was also set to extend from 435,000 to 650,000 miles. Now the EPA proposes retaining the shorter warranty and delaying the longer useful-life requirement.
Therefore, that is not decorative paperwork.
A longer regulatory useful life concerns how long an engine must continue meeting emissions requirements. Likewise, an emissions warranty determines how much of the failure risk remains with the manufacturer instead of landing in the fleet owner’s lap with an invoice attached.
Consequently, weakening those provisions does not merely shave a few pages from a manual. It changes who pays when emissions hardware fails and how long the cleaner performance must endure.
The tailpipe target can stay framed on the wall.
Meanwhile, the accountability clock gets shorter.
Jennifer Rumsey Discovers Customer Choice In The Warranty Department
Rumsey called the proposed emissions-warranty change “a really big deal”.
She framed the reduction as flexibility. Fleets would no longer have to buy an emissions warranty covering the product’s whole life upfront. Some customers could still choose longer protection, she explained, but others would have a choice.
Choice is a gorgeous corporate word.
If the manufacturer must cover the risk, it is an inflexible mandate. Once the customer may need to purchase that protection separately, it becomes freedom.
The warranty did not disappear, you see.
It simply left the regulation and reappeared near the fucking options list.
Furthermore, Cummins knows the value of extended emissions coverage. The company’s 2024 Clean Air Act settlement requires it to provide an extended warranty for repaired Ram 2500 and 3500 trucks after the EPA said Cummins had configured software features as illegal defeat devices.
That case involved a different vehicle programme and a remedial settlement, not the new heavy-duty EPA27 warranty rule. TCAP will not pretend otherwise.
Nevertheless, the contrast is magnificent.
In the settlement, extended coverage helps ensure repaired vehicles continue meeting emissions standards after software reduced or deactivated controls during normal driving. At the state fair, however, mandatory long-term emissions coverage became a costly restriction from which customers deserved liberation.
Cummins apparently likes extended warranties best when a federal consent decree has already carried them to the table.
The Company Had Already Written The Reliability Sermon
Cummins spent 2025 explaining why its EPA27 technology was ready.
Its own technical material says the Twin Module aftertreatment system for the X10 and X15 was designed to cut NOx by more than 75% against current regulations while maintaining durability and efficiency. Moreover, Cummins described the design as an evolution of familiar diesel oxidation catalyst, particulate-filter and selective-catalytic-reduction technology used since 2010.
Not entirely new, said Cummins.
Built on a proven foundation, said Cummins.
Reliable and effective, said Cummins.
Then July 2026 arrived wearing a deregulation badge, and suddenly everybody needed more time for real-world validation.
There is nothing inherently improper about phasing a complicated product launch. Engineers test, manufacturers ramp production and customers deserve reliable equipment. Still, Cummins cannot sell “proven foundation” to the public, “ready for 2027” to investors and “do not rush us” to regulators without someone eventually laying the brochures beside one another.
TCAP has a large table.
Cummins EPA27 Lobbying Becomes A Production Plan
Consequently, two weeks after the fairground announcement, Cummins published its updated Model Year 2027 launch plan.
The company said it intended to use the EPA proposal’s “implementation flexibilities” for a measured transition. Limited X15 production would begin in January 2027, with full production expected in the fourth quarter. The X10 would also start on a limited basis in January before reaching full production in the third quarter. During those transitions, current-generation engines would remain available.
Cummins even warned that its product plans might change if the final rule differed materially from the proposal, including changes to the transition provisions.
In other words, that sentence removes any need for interpretive dance.
The flexibilities are not some abstract favour to the trucking industry. Cummins has already built them into its production planning and publicly said it is counting on them.
Rumsey insists the destination has not changed.
Perhaps not.
However, the convoy has acquired additional lay-bys, a softer warranty, a delayed durability clock and a toll booth where certain non-compliant engines may purchase temporary passage.
Destination Zero has always had a fucking scenic route. Haven’t they already choked everyone enough?
Nearly One Million Reasons For A Little Less Trust
Cummins does not approach emissions regulation with a spotless file.
For example, in 2024, the company agreed to a record $1.675 billion civil penalty under the Clean Air Act. According to the EPA, Cummins placed illegal defeat-device software in 630,000 model-year 2013–2019 Ram trucks. Roughly 330,000 additional 2019–2023 vehicles contained undisclosed auxiliary emissions-control devices.
Moreover, the case affected the emissions systems of nearly one million vehicles.
The EPA said the software could activate full controls during compliance testing, then reduce or deactivate those controls during other normal operation. As a result, vehicles emitted NOx at levels far above the applicable limits.
Cummins denied the government’s allegations and admitted no liability under the consent decree. It still agreed to the penalty, recalls, extended warranties, mitigation work and corporate reforms.
Therefore, when Cummins supports shorter mandatory emissions coverage and easier implementation provisions two years later, scepticism is not radical activism.
It is basic file management.
The company already supplied a two-billion-dollar lesson in why laboratory compliance, real-world performance, disclosure and long-term accountability belong in the same room. Now it wants the public to trust that a surviving headline limit will remain sufficiently muscular after the warranty and useful-life provisions lose weight.
Of course it fucking does.
The People Breathing The Flexibility
The coalition letter is not arguing over an accounting convention.
Its signatories say heavy-duty trucks represent only 6% of vehicles on the road but account for 59% of transport-sector NOx and 55% of particulate pollution. Those pollutants contribute to asthma, heart disease, strokes and premature deaths, with communities near highways, warehouses and ports carrying a disproportionate burden.
Truck drivers also spend their working lives inside the product environment that manufacturers invoke whenever they need a sympathetic face for regulatory relief.
At the fair, industry leaders discussed affordability, uptime and safety. Of course, those concerns are legitimate. A truck unexpectedly derating because of a faulty DEF sensor can create danger and economic harm.
However, fixing a defective inducement system does not require pretending every accompanying rollback is a gift to drivers. Nor does lowering the manufacturer’s warranty burden automatically lower the lifetime cost of ownership. Sometimes an expense has merely crossed the table.
Manufacturers save.
Customers choose.
Everyone else breathes whatever survives the transaction.
Talk Clean, Lobby Dirty, Publish Destination Zero
GreenLatinos called its account “Truck Manufacturers Talk Clean, Lobby Dirty”.
Fair enough.
Cummins publishes decarbonisation stories, markets “Higher Efficiency, Lower Emissions” engines and signs every newsroom pudding with Destination Zero. Meanwhile, its CEO appears beside an administration celebrating regulatory retreat, praises the warranty reduction and then announces a production plan that expressly depends on the proposed flexibilities.
None of this resembles surprise.
It resembles a business using every available channel for its intended purpose. Sustainability language protects the brand. Investor assurances protect confidence. Trade associations apply pressure. Friendly regulators convert that pressure into flexibility. Finally, corporate communications explains that the destination never changed while the timetable, warranty and enforcement architecture are quietly sent downstairs.
Finally, the twenty-four organisations want Cummins, PACCAR and Daimler to reverse course and tell the American Trucking Associations to withdraw its support.
TCAP would also like Cummins to answer a few questions.
If the EPA27 technology was reliable and ready, which precise requirements became unattainable? How much of the claimed customer saving comes from transferring warranty risk away from manufacturers? How many current-generation engines does Cummins expect to sell under the transition flexibilities? Finally, why should communities trust Cummins to favour durable real-world NOx control after the largest Clean Air Act civil penalty in history?
Do take your time, Jennifer.
The engines were apparently ready before the answers.
Cummins calls this a measured transition.
The advocates call it weakened implementation.
TCAP calls it what it usually calls a Cummins sustainability sermon once the lobbying paperwork arrives:
The fucking invoice.
Lee Thompson – Founder, The Cummins Accountability Project
Source List
- Charged EVs – Advocates Urge PACCAR, Cummins And Daimler To Stop Lobbying To Water Down Heavy-Duty NOx Standards
- GreenLatinos – Truck Manufacturers Talk Clean, Lobby Dirty
- Coalition Letter To PACCAR, Cummins And Daimler Truck – 20 July 2026
- US EPA – Proposed Revisions To The Heavy-Duty NOx Rule
- US EPA – 2023 Heavy-Duty Engine And Vehicle Standards
- ACT News – EPA Proposal To Revise 2027 Heavy-Duty Engine Compliance Rules
- Cummins – Phased Model Year 2027 Product Launch Plan
- Cummins – EPA27 Twin Module Aftertreatment System
- Cummins – Exploring The 2027 X15 Engine
- US EPA – 2024 Cummins Vehicle Emission-Control Violations Settlement
- American Trucking Associations – Request To Delay The Heavy-Duty NOx Rule Until 2031