California Officially Bans Pre-2010 Diesel Trucks, Buses

Matt Posky
by Matt Posky

california officially bans pre 2010 diesel trucks buses

In 2008, the California Air Resources Board (CARB) approved legislation designed to curtail emissions from older trucks and buses operating within the state. Known as the “Heavy Duty Vehicle Greenhouse Gas Emission Reduction” measure, the law originally called for long-haul truckers to install specialized tires and aerodynamic devices on their trailers that improved fuel economy. However, it’s gone through numerous updates over the years, eventually making it illegal to even operate certain vehicles equipped with the wrong kinds of engines. The latest update bans any truck with a gross vehicle weight rating (GVWR) over 14,000 pounds using an engine manufactured before 2010.

These bans aren’t new. California began prohibiting older trucks and buses from hitting the road over a decade ago – and updates approved by CARB have kept pace to ensure vehicles utilizing older motors aren’t allowed to go anywhere. In 2020, the cutoff for diesel engines applied to anything manufactured prior to 2004. This year, the line has been drawn at 2010.

While the laws don’t technically prohibit anyone with a vehicle registered in another state from rolling through California with an older motor, the state will refuse the registration, renewal, or transfer of anything that doesn’t comply with the updated rules. However, the board has said it would also like to try and stop out-of-state vehicles from using older engines and has been working with the Environmental Protection Agency to enforce the rule on trucks not from California. Meanwhile, CARB has an enforcement unit of its own that will randomly audit in-state fleets, conduct inspections, and issue citations.

Back in 2022, CARB estimated that the latest rule change would impact roughly 200,000 buses and over 70,000 trucks currently in operation within the state. But it’s all allegedly for the greater good, as large trucks and buses are responsible for more per capita emissions than passenger cars.

"When we passed the regulations in 2008, it was to reduce community exposure of toxic air contaminants, it is 100 [percent] to protect public health," Gerald Berumen, a spokesman for the air resources board, told KCRA-TV in an interview.

The end goal is to keep the prohibition rolling until California’s 2035 diesel engine ban mandate comes into effect.

With combustion-engine bans becoming highly trendy in some parts of the country, pushback has likewise become commonplace. Critics have noted that these rules effectively force truck operators to purchase new engines. This disproportionately disadvantages independent operator-owners and smaller shipping companies with less money than the big boys. CARB has suggested compliance is easy, however, claiming that many operators and fleets have already complied with the new rules – with over 1.5 million vehicles being fitted with newer engines.

Not that they were left with much of a choice.

Additional criticisms focus on just how environmentally sound the scheme actually is. While swapping in a new motor should result in cleaner exhaust emissions, it also produces a lot of pollution upfront by requiring another motor to be manufactured as a replacement. This requires more raw materials, loads of shipping, and ultimately leads to a functional motor being scrapped. Some have also complained that CARB is out of touch and doesn’t accurately represent the needs of Californian citizens. Members of the board aren’t elected but appointed by the Governor and confirmed by the state Senate, typically with the 16-person air resources board making decisions on behalf of the citizenry.

But it’s also true that the topography of California leaves portions of the state in a bowl that traps more particulate matter. This is one of the reasons Los Angeles has had ongoing smog problems and regulatory boards are so aggressive. Though that may not be a sound justification for statewide engine prohibition.

Jalopnik has noted that there will be exemptions for the rule and TFLTruck posted the official list of compliance options earlier this month. For example, if you drive your big rig fewer than 1,000 miles per year (presumably because it’s a collectible or historic vehicle) then you’re off the hook entirely. Fleets can likewise install the latest particulate matter filters in their engines to buy themselves some time before having to purchase entirely new engines. Agricultural vehicles yielding low miles are also given some leeway. But the mileage restrictions have gotten more strict for 2023.

Still, if you happen to be driving a tractor-trailer or people-mover within the state as part of your profession, there’s likely no way around having to purchase a new motor. Granted, rebuilds and replacements are par for the course in the trucking industry. But these rules may mean you’ll be spending more sooner than you would have wanted to.

[Image: Vitpho/Shutterstock]

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3 of 110 comments
  • Joh65690876 Joh65690876 on Jan 23, 2023

    One medium sized California forest fire will produce more particulate matter in 2-3 days than all of the diesel fuelled trucks and buses produce in a year.

    • EBFlex EBFlex on Jan 23, 2023

      Context and perspective is not allowed here

  • Joh65690876 Joh65690876 on Jan 25, 2023


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