Heavy Duty Trucking Logo
MenuMENU
SearchSEARCH

Stricter Truck Emissions Standards are a Gorilla of a Monkey Wrench [Commentary]

CARB may be able to quickly squeeze heavy-truck emission limits yet tighter, explores HDT's Contributing Washington/Business Editor David Cullen in the Passing Zone column.

David Cullen
David Cullen[Former] Business/Washington Contributing Editor
Read David's Posts
March 27, 2023
Stricter Truck Emissions Standards are a Gorilla of a Monkey Wrench [Commentary]

CARB may be able to quickly squeeze heavy-truck emission limits yet tighter, explores HDT's Contributing Washington/Business Editor David Cullen in the Passing Zone column.

Graphic: HDT

3 min to read


If approved, a request by California to enact markedly stricter heavy-truck emissions standards than those set by the federal government will massively disrupt the already-fraught view trucking holds of the upcoming rules laid out by the Environmental Protection Agency.

Ad Loading...

This gorilla of a monkey wrench will vigorously shake the tightrope of a timeline that truck and engine manufacturers are navigating to ensure compliance with the new regulations while delivering the performance expected by fleets.

Disrupting the engineering already in motion by changing the rules this late in the game would ripple down the manufacturing supply chain to gum up the works. That would upset fleet plans to replace old trucks with new in the face of another pre-buy explosion.

Ad Loading...

It’s not a done deal, but news reports in the general media earlier this month strongly suggested that approval was imminent. Washington Post reporter Anna Phillips is credited with having broken the news on March 20. EPA “intends to grant California ‘waivers’ to enforce environmental rules that are significantly tougher than federal requirements and that state regulators have already approved,” she reported.

But wait, there’s more bad news. Whenever California secures waivers of preemption, per the California Air Resources Board, the federal Clean Air Act “allows other states that are or have been noncompliant with federal ambient air quality standards to adopt California’s standards as their own.”

To date, 13 states and the District of Columbia have adopted all or part of certain California emission standards.

Within three days of the Post story, the American Trucking Associations issued a blistering press release on the waiver request. ATA keyed in on how changing upcoming emissions rules now could derail the supply chain that drives truck production.

“Our industry hopes these reports aren’t true,” stated ATA President and CEO Chris Spear. “The state and federal regulators collaborating on this unrealistic patchwork of regulations have no grasp on the real costs of designing, building, manufacturing, and operating the trucks… As we learned in the pandemic, the supply chain can be a fragile thing — and its integrity must be preserved at the national level.”

Ad Loading...

One day after ATA spoke out, word came that a new advocacy group of trucking stakeholders had been formed to “get to zero emissions in a responsible and feasible manner.” The Clean Freight Coalition consists of motor carriers, truck makers, and truck dealers. Its founding members include ATA, the Truckload Carriers Association, and the Truck & Engine Manufacturers Association (EMA).

The Clean Freight Coalition has twin interrelated goals: Advocate for public policies that transition toward a zero-emission future while assuring “affordable and reliable freight transportation and [protecting] the nation's supply chain.”

Perhaps the launch of CFC stemmed from last summer’s decision by EMA to withdraw its lawsuit against CARB that contended the agency did not provide enough lead time for truck and engine makers to meet its 2024 emission standards.

That EMA legal action had spurred substantial blowback by environmental groups and some of its own members, including Cummins, Ford, and GM, that publicly stated they did not support the litigation. For example, a joint letter sent by 34 regional and national environmental groups upbraided EMA’s member leadership, including the heads of Daimler Truck NA, Navistar, Paccar, and Volvo Group NA, for “harmful EMA lobbying and disinformation campaigns designed to slow or stall the transition to cleaner trucks.”

So, it would seem that the further development of engines and trucks to comply with 2024 and 2027 diesel emission standards is not likely to go as anyone has hoped. At this point, whether it will be a race back to the drawing boards or a steady push to the current finish line is anyone’s bet.

Ad Loading...

This commentary appears in the April 2023 issue of Heavy Duty Trucking.

More from David Cullen's Passing Zone column: M&A in Trucking: A Tale of Two Year

Subscribe to Our Newsletter

More Fuel Smarts

Video still of Volvo's Duane Tegels explaining the Volvo D13 diesel engine for EPA 2027 emissions
Equipmentby Deborah LockridgeSeptember 16, 2026

How Volvo Updated Its D13 for EPA 2027 [Watch]

Volvo’s updated D13 promises lower emissions without sacrificing performance or fuel economy. Take a closer look at what changed inside the engine in this HDT Spotlight video.

Read More →
Collage of fuel options for trucks - renewable diesel, renewable natural gas, diesel, and electric
Fuel Smartsby StaffSeptember 15, 2026

Diesel Price Spike Shortens Payback for Natural Gas Trucks, Report Says

Energy Vision estimates fleets could recover the higher purchase price of an RNG-fueled Class 8 tractor in 1.3 to 2.8 years under current fuel-price scenarios.

Read More →
Illustration showing the Calstart, Forth, and Catalyst Mobility logos
Fuel Smartsby StaffSeptember 14, 2026

Calstart Becomes Catalyst Mobility, Reflecting Broader Focus

Calstart is now Catalyst Mobility, reflecting the nonprofit’s growing national role in clean transportation, including zero-emission trucks, infrastructure and incentive programs.

Read More →
Ad Loading...
Illustration with oil wells, dollar bills, and a diesel fuel pump
Fuel SmartsSeptember 9, 2026

Record Diesel Prices Squeeze Trucking Fleets

Average U.S. diesel prices have climbed to nearly $6 a gallon, surpassing the 2022 record as tight refinery capacity and Middle East disruptions keep fuel costs elevated.

Read More →
A red engine part
SponsoredSeptember 9, 2026

How Fuel Delivery Shapes Engine Performance

Fuel delivery depends on more than what happens at the injector. For fleet, maintenance and technical professionals, looking at the full path from pump to injector can provide useful context for understanding engine performance.

Read More →
Port of Newark EV truck charging station.
Equipmentby News/Media ReleaseSeptember 8, 2026

East Coast Port Launches $45M Electric Truck Push

The Port Authority of New York and New Jersey announced millions in incentives for zero-emission drayage trucks, yard tractors, and new charging hubs near the port.

Read More →
Ad Loading...
Fuel Smartsby StaffAugust 31, 2026

California Bill Could Shed Light on Electric Truck Prices

Why do battery-electric Class 8 trucks remain so expensive? A California bill headed to Gov. Gavin Newsom would give fleets and state agencies more visibility into what manufacturers charge.

Read More →
Illustration of Freightliner Cascadia on highway with engine cutaway
Equipmentby Deborah LockridgeAugust 27, 2026

Detroit Opens Orders for EPA 2027 Engines

Detroit isn’t starting from scratch to meet EPA 2027 diesel emissions standards. Its Gen 6 DD13 and DD15 engines keep much of today’s platform while updating the fuel and aftertreatment systems.

Read More →
Group of people and zero-emission trucks during ceremony announcing a West Coast ZEV corridor.
Fuel Smartsby News/Media ReleaseAugust 26, 2026

Zero-Emission Truck Corridor Planned for West Coast

California, Oregon, Washington, British Columbia and Baja California are coordinating plans for truck charging and hydrogen fueling from Canada to Mexico.

Read More →
Ad Loading...
YouTube thumbnail showing Kenworth T880e electric truck and KW marketing director Kyle Kimball.
Equipmentby Deborah LockridgeAugust 25, 2026

A Closer Look at Kenworth’s Electric T880E Vocational Truck [Video]

Learn more about Kenworth's T880E battery-electric vocational truck at the Paccar Technical Center, including its range, applications, upfitting considerations, and PTO options, in this HDT Spotlight video.

Read More →