Starting in January 2025, there is a new law that will let the California diesel ban go into effect, and this has several groups up in arms and a lot of outlets spreading misinformation about what this law really means and how it affects you, the consumer. So we dig into this new law, as well as several other applicable rules surrounding diesel and gasoline engine vehicle sales.
California diesel engine ban
So, what’s really going on here? Well, let’s back up a bit. California, through a special EPA waiver, has the authority to set its own emissions rules. These rules are created through the California Air Resource Board (CARB), and 17 states, including the District of Columbia, have adopted some or all of these rules. So, the ban doesn’t necessarily just affect California.
CARB reports these states have opted into at least part of the CARB regulations: Colorado, Connecticut, Delaware, Maine, Maryland, Massachusetts, New York, Pennsylvania, Rhode Island, Oregon, New Jersey, Minnesota (model year 2025), Nevada (model year 2025), New Mexico (model year 2026), Vermont, Virginia (model year 2025), and Washington.
It is unclear which of these states will move forward or back off the CARB emissions rules.
The rules impacting diesel and gasoline engines are divided into three pieces: the Advanced Clean Truck Act, the Advanced Clean Fleet Act and the Low NOx Heavy-Duty Omnibus Regulation. Here’s a (very) brief explainer of these rules.
California Advanced Clean Truck (ACT) Regulation, which takes effect January 1, 2025, aims to transition to zero-emission medium- and heavy-duty Class 2b vehicles by limiting the amount of diesel- and gasoline-engined vehicles that can be sold in that state.
Per this law, manufacturers must sell zero-emission trucks as a percentage of their annual California sales:
- 2024 model year: 5–9% of sales must be zero-emission vehicles (ZEVs) depending on the truck category.
- 2035: 55% of Class 2b–3 truck sales, 75% of class 4–8 straight truck sales, and 40% of truck tractor sales must be zero-emission.
For reference, Class 2b trucks are 2500 or 3/4-ton models and vans, with a GVWR of 8,501 to 10,000 pounds. The larger trucks are often found in fleets for U-Haul, utility companies, ranchers, farmers, wine producers, etc.
California Advanced Clean Fleet Act, which took effect on January 1, 2024, mandates that large truck fleets operating in California gradually transition to zero-emission vehicles (ZEVs) by phasing in the purchase of electric trucks and ultimately requiring all new medium and heavy-duty vehicles sold in the state to be zero-emission by 2036
California’s Low NOx Heavy-Duty Omnibus Regulation (HDO), which took effect on December 22, 2021, is a set of standards and requirements that reduce the amount of nitrogen oxide (NOx) emissions from heavy-duty engines.
These acts, with various enforcement dates, will eliminate the sale of most diesel engines in heavy-duty and medium-duty trucks by the year 2035. To be clear, these laws don’t ban the use of these trucks if they’ve already been purchased, but new sales will be subject to the above regulations.
Therefore, companies are now pre-buying diesel trucks to stockpile for when the rules take effect, according to Allen Shaeffer, executive director of the Engine Technology Forum.
“Things are just a mess right now,” Shaeffer said in a video interview. “Zero emission and battery electric trucks are going to make some inroads in the trucking industry there’s no question about it but they’re not going to do it in the time frames and percentages that people have anticipated. Especially as fast as California’s rules have anticipated.”
Is this an EV mandate or a ICE ban?
There’s been a long running debate over whether this legislation is an EV mandate or not.
Karen Bailey-Chapman, Senior Vice President, Public and Government Affairs for the Speciality Equipment Market Association (SEMA), sees it quite clearly as a ban.
“What else would you call this?” she said. “I think ban is the appropriate word because we just came through the political cycle, and we were very active about educating voters about these EV mandates, both the federal as well as the California ones.
“There’s a point in which some media were trying to push back saying there is no EV mandate, and my response is: Okay, then we’ll call it what it is. It’s an internal combustion engine ban. We were being nice by calling it an EV mandate, but we we’ll call it what it is.”
Lawsuits over the rules
Several organizations have sued over these rules including the National Truck Equipment Association (NTEA) and SEMA, which have filed a joint lawsuit.
They contend California’s laws amount to a ban on all engines and far exceeds the state’s authority.
“Ultimately, work trucks must be available, capable and affordable. It is important to reach this desired outcome using a sensible and cost-effective approach so our member businesses can continue to build and supply the vehicles that are essential for commerce,” said NTEA President & CEO Steve Carey in a press release. “Left unchecked, the current suite of California regulations will severely curtail the ability of work truck users to obtain the vehicles they need to successfully and efficiently carry out their vital missions and support ongoing business operations in critical industries such as public works, utilities and telecommunications, emergency response, construction, food and agriculture, last-mile delivery and many others.”
Valero’s Diamond Alternative Energy and related groups presented a case to the U.S. Supreme Court argued the new emissions rules reduce the amount of demand for liquid fuels causing financial harm.
Other groups like the RV industry Association say it could have a significant impact on their industry. Because there are no certified zero-emissions chassis rated for motorhomes, the California Air Resources Board’s (CARB) ACT regulation could impact the availability of motorhomes in California beginning January 1. Motorhomes can still be sold either through utilizing the credit market or generating a carry forward deficit that will have to be offset by the chassis manufacturer credits within three years.
What about Ford, GM and Ram heavy-duty trucks?
We reached out to the Detroit 3 to get their views on these California regulations and how it could impact their large commercial fleet operations. These automakers rely on commercial sales as a significant part of their business.
Here is what we heard from each of them:
GM: “While the CARB Advanced Clean Trucks (ACT) rule ramps up to a 100% ZEV manufacturer mandate in 2036, there is no ban on GM’s internal combustion engine vehicles in 2025. GM will continue selling ICE chassis-cab and low cab-forward models in all 50 states,” said Sean Szymkowski, senior manager, Chevrolet Silverado Communications
Ford: “In the 2025 calendar year, Ford Pro will expand restriction of diesel engine availability on 26MY F-650, F-750, and 25MY Super Duty F-600 (said otherwise, any Super Duty trucks over 19,500 lbs.) as a key part of the Ford strategy to offer customers the freedom to choose vehicles that meet their needs while continuing to significantly lower carbon and other air emissions over time,” said, Elizabeth Kraft, from Ford North America Commercial Vehicle Communications. “We plan to transition impacted diesel customers to other high-quality options in Ford Pro’s vehicle lineup that meet their needs; combined with Ford Pro software, fleet managers can access valuable insights, like excessive idling, that can help increase fleet productivity, improve sustainability and lower maintenance and fuel costs.”
Ram: No comment.
The bottom line
While the initial impact of these rules will impact fleets, there will likely be a trickle-down effect for consumers. Issues like limited to no availability for diesels, higher costs for goods and limits on which new RVs are sold could all happen within the first few months of 2025.
Watch this video with full interviews for more information:
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