Heavy Duty Trucking Logo
MenuMENU
SearchSEARCH

What Does CARB Emissions Compromise Mean for Trucking?

Is the deal inked between the California Air Resources Board and major truck and engine makers on state emissions standards good news for the trucking industry?

Deborah Lockridge
Deborah LockridgeEditor and Associate Publisher
Read Deborah's Posts
July 7, 2023
What Does CARB Emissions Compromise Mean for Trucking?

“The trucking industry continues to be in the crosshairs of communicating all of these to a customer base that won’t entirely understand the ramifications of such rhetoric-filled rules." — TCA President Jim Ward

Image: HDT/Canva

7 min to read


What regulators are calling a historic and unprecedented agreement between the California Air Resources Board and major truck and engine makers should provide some much-needed flexibility for truck and engine makers in meeting the state’s stringent zero-emissions regulations.

However, associations representing trucking companies are not happy with the agreement and expressed concern about what this will actually mean for the fleets that must buy the trucks.

Ad Loading...

The agreement announced July 6 creates a Clean Truck Partnership between CARB, the Truck and Engine Manufacturers Association, and major medium- and heavy-duty truck and engine makers.

The news comes as California prepares to implement rules requiring a phased-in transition toward 100% sale and use of zero-emissions technology for medium- and-heavy duty vehicles under CARB’s Advanced Clean Trucks and Advanced Clean Fleets rule by 2045.

In March, the Biden administration approved California’s waiver under the federal Clean Air Act that allows the state to become the first in the world to require zero-emissions technology for trucks.

Ad Loading...

The Clean Truck Partnership agreement provides flexibility for manufacturers to meet emissions requirements while still reaching the state’s climate and emission reduction goals, according to an announcement from CARB.

According to the Washington Post, the deal is the result of more than three months of negotiations between the industry and the California Air Resources Board.

One of the aims of the agreement is to avoid more litigation. Last year, the Truck and Engine Manufacturers Association withdrew a lawsuit against CARB, challenging the timing of its Heavy-Duty Engine and Vehicle Omnibus Regulation adopted in late 2021.

The lawsuit alleged the agency had not provided enough time for truck and engine makers to meet those standards, scheduled to go into effect in 2024 — only two years of lead time. EMA’s suit said the federal Clean Air Act required manufacturers to have at least four full model years of lead time before implementing new heavy-duty engine emission standards.

While the lawsuit was intended to address the short lead time, not the actual emissions standards, it drew the ire of environmental groups and saw some EMA members distancing themselves from it, resulting in the suit’s withdrawal.

Ad Loading...

More About the Clean Truck Partnership Deal

Jed Mandel, president of the Truck and Engine Manufacturers Association, known as EMA, explained that “through this agreement, we have aligned on a single nationwide nitrogen oxide emissions standard, secured needed lead time and stability for manufacturers, and agreed on regulatory changes that will ensure continued availability of commercial vehicles.”

CARB agreed to give truck and engine makers more time to meet new requirements and more protection for legacy engines. The agreement raises the caps on legacy engines, letting truck and engine makers continue to sell more diesel engines over the next three years if they sell enough zero-emission vehicles to offset the emissions.

California’s existing nitrogen oxide pollution standards will be relaxed so they align with the federal government’s rules. The difficulties of meeting multiple emissions standards has been a big complaint of truck and engine makers and trucking lobbyists.

The state agreed that in the future, it will provide at least four years lead time before imposing new standards and that any new mandates will stay in place for at least three years before they can be changed.

In return, the truck and engine makers agreed that they will meet California’s zero-emission vehicle targets and air pollution limits — even if they are later overturned in court. The OEMs agreed to meet California standards, no matter what the outcome of any litigation challenging EPA Agency waivers or authorizations for those regulations or of CARB’s overall authority to implement those regulations.

Ad Loading...

What hasn’t changed is CARB’s requirement that half of all heavy-duty trucks sold in California will be electric by 2035. 

The agreement applies to Class 8 tractors as well as heavy-duty pickups weighing more than 14,000 pounds. In addition to EMA, the Clean Truck Partnership includes Cummins Inc., Daimler Truck North America, Ford Motor Company, General Motors Company, Hino Motors Limited Inc., Isuzu Technical Center of America Inc., Navistar Inc., Paccar Inc., Stellantis N.V., and Volvo Group North America.

Other states could be affected by this agreement, because some states adopt California’s air pollution rules, which go beyond federal Environmental Protection Agency standards. And it could mean even more states adopt California’s same standards because they wouldn’t have to worry about whether the rules would be upheld in court.

The agreement also calls for the parties to work together to resolve issues that may warrant regulatory amendments. And the parties are to actively promote the infrastructure development needed to support the successful implementation of CARB’s Advanced Clean Trucks regulation.

‘Restores Some Sanity’

The Diesel Technology Forum was not a signee to the agreement, but Executive Director Allen Schaeffer told HDT that at first look it appears to be “a significant breakthrough for industry overall.”

Ad Loading...

“It will give truckers more choices of technology in California than they may otherwise have had,” Schaeffer said, pointing to comments he’s heard from manufacturers that the rules would significantly limit their product offerings in California in future years.

“It also restores some sanity, frankly, to the regulatory process,” Schaeffer said. “It recognizes this this is a national industry that crosses state borders as a matter of practice, and that we need to come together to have a uniform national approach for the better of all folks, not just Californians.

“I also think that California recognized they were out on a limb with some of their interpretations of lead time and stability, and sort of flaunting some of the Clean Air Act provisions there," he added.

“So do we want to spend the next couple years litigating all that in court, or do we want to have a thoughtful glide path for manufacturers and truckers to get the best technology that does the job for their business?”

Is What’s Good for Truck Makers Good for Their Customers?

However, groups representing trucking fleets aren’t happy with the deal.

Ad Loading...

American Trucking Associations President and CEO Chris Spear appeared to raise the possibility of litigation from the association.

“We’ve long advocated for a single, national standard that respects and preserves interstate commerce,” he said in a statement. “However, the trucking industry shouldn’t be strong-armed by the government into an agreement with such terms.

“Our association represents motor carrier members — the paying customers who will inherit the costs of this agreement — and we will not roll over nor relinquish our right to litigate with any party when our interests are threatened.”

The Truckload Carriers Association had similar concerns.

“Unfortunately, with this agreement, the motor carrier and its drivers will experience the pain points of this ill-suited compromise,” said Jim Ward, TCA president. “As we have continued to point out, the issues of reliability, affordability and achievability of these regulations must remain at the forefront of these conversations.

Ad Loading...

“The trucking industry continues to be in the crosshairs of communicating all of these to a customer base that won’t entirely understand the ramifications of such rhetoric-filled rules. 

“Concerns of equipment reliability, infrastructure uncertainty and high cost of these trucks will reveal themselves as we move closer to these deadlines, and our government officials will once again be forced to explain the shortcomings of the nation’s supply chain when now is the actual time to resolve these matters to develop environmentally friendly trucks that would continue to deliver this nation.”

The Clean Freight Coalition, formed earlier this year with a founding group of five associations (ATA, EMA, TCA, American Truck Dealers and National Tank Truck Carriers), also weighed in, questioning the benefits of the agreement.

"The unachievable standards and timelines set forth by California regulators jeopardize the entire supply chain and risk truck dealers having limited compliant products to sell and fleets holding onto their older trucks longer," said CFC Executive Director Jim Mullen in a statement.

“The CFC questions the benefits of this agreement," he said. "Policymakers could make an immediate impact on truck emissions by providing incentives for motor carriers to refresh their fleets with newer, more environmentally friendly trucks. For instance, eliminating the Federal Excise Tax on heavy trucks would provide immediate benefit by reducing emissions while improving roadway safety with trucks equipped with the latest technologies. 

Ad Loading...

“A patchwork of state regulations disrupts the trucking industry and our nation’s supply chain. The CFC will continue to advocate for a sustainable and affordable transition to a zero-emission future which protects the supply chain and does not pass the financial burden onto the hundreds of millions of American households and business consumers who depend on goods shipped by trucks.”

Equipment Editor Jim Park contributed to this story.

Updated 5:15 EDT to add CFC remarks.

Read more about electric trucks in California:
Schneider's Electric Heavy-Duty Trucks Start Off on Regional Routes

More Fuel Smarts

Illustration of exhaust aftertreatment system on an AI-inspired blue background and a green fuel pump nozzle in the foreground.
Maintenanceby Deborah LockridgeJune 15, 2026

New Agentic Predictive Maintenance Report Demonstrates How Degraded Aftertreatment Systems Waste Fuel

Questar analyzed a large mixed-class fleet and discovered it was wasting as much as $30 in fuel per vehicle, per day, because of mechanically degraded aftertreatment systems.

Read More →
Amazon electric cargo bike on New York City street
Fleet ManagementJune 15, 2026

New York City's Microhub Project is Delivering Results

Trucking, last-mile delivery companies, and environmental advocates like what they are seeing so far with New York's microhub program.

Read More →
Red Kenworth truck pulling Paper Transport trailer
Fuel Smartsby Deborah LockridgeJune 2, 2026

Lessons Learned About Alternative Fuels: Start Small, Stay Flexible

Practical advice on adopting alternative fuels and ZEVs from HDT's 2026 Top Green Fleets, from renewable diesel and natural gas to electric trucks.

Read More →
Ad Loading...
Composite image of different angles of the Kempower charger
Fuel Smartsby News/Media ReleaseMay 29, 2026

Kempower Adds Flex EV Charger to Help Support Transition to Megawatt Charging

The Kempower Mega Satellite Flex has both a CCS and MCS connector, allowing operators to serve both types of heavy-duty vehicles.

Read More →
White Hino Le electric tractor on show floor
Equipmentby News/Media ReleaseMay 26, 2026

Hino Adds Electric Class 6/7 Truck

Hino says the Le Series is an important step in the company's efforts to reduce environmental impact and support its customers’ sustainability goals.

Read More →
Sigma Powertrain BEV transmission.
Fuel Smartsby Jack RobertsMay 26, 2026

Can Multi-Speed EV Transmissions Solve Heavy Trucking’s Biggest Electric-Vehicle Problems?

A startup called Sigma Powertrain believes purpose-built multi-speed gearboxes can boost efficiency, reduce battery size and improve gradeability for heavy-duty battery-electric trucks.

Read More →
Ad Loading...
Red Hendrickson e-axle at ACT Expo booth
Equipmentby News/Media ReleaseMay 22, 2026

Hendrickson Debuts Electraax E-Axle for Medium-Duty Trucks

Developed with Driventic, Hendrickson's new integrated e-axle is designed to improve efficiency, reduce weight, and extend range in Class 6-7 EV applications.

Read More →
Fueling trucks.
Fuel SmartsCover Storyby Deborah LockridgeMay 18, 2026

50 Ways Fleets Can Cut Fuel Costs Now — Without Buying New Trucks

Fuel savings don’t come from one big change. They come from dozens of small ones. Here’s how leading fleets are stacking gains across drivers, routing, maintenance, and more.

Read More →
Collage of HDT Top Green Fleets with logo
Fuel Smartsby Deborah LockridgeMay 18, 2026

Top Green Fleets 2026: How Fleets Are Reducing Emissions in the Real World

What works in sustainable trucking today? Heavy Duty Trucking's Top Green Fleets are finding practical ways to cut fuel use, reduce emissions, and keep freight moving.

Read More →
Ad Loading...
Tesla Semi electric truck on display at ACT Expo
Fuel Smartsby News/Media ReleaseMay 13, 2026

California Launching $1 Billion Electric Truck Rebate Program

CARB says the California Clean Fuel Reward program will begin offering point-of-sale rebates of up to $120,000 for electric commercial trucks starting June 26.

Read More →