On-Road Vehicles

Eligible vehicle types include heavy-duty trucks and buses, transit buses, solid waste collection vehicles, public agency and utility fleet vehicles and emergency vehicles (however, emergency vehicles are only eligible under the replacement project type).

On-Road Vehicles:

Fleets must be fully compliant with all applicable fleet regulations.  Eligible project types include vehicle replacement and repower/conversion projects; on-road retrofit projects will be considered on a case-by-case basis. The proposed vehicle must be in the same weight class as the existing vehicle (LHD, MHD or HHD).  The engine must be certified to the applicable heavy-duty intended service class as shown on the engine certification Executive Order.  However, the following cases may be allowed: 1) MHD engines may be installed in HHD vehicles with GVWR up to 36,300 lbs. (10 percent higher than 33,000 lbs. GVWR) with written warranty verification by engine and chassis manufacturer, or 2) HHD engines may be installed in MHD vehicles if necessary for vocational purposes but only if the GVWR are within 10 percent of the HHD intended service class (i.e., GVWR of 29,701 lbs. or greater).

Executive Orders for on-road vehicles may be downloaded at:

Emergency Vehicles:

Authorized emergency vehicles, as described in California Vehicle Code 165, including but not limited to fire apparatus, pumpers, ladder trucks, water tenders, and prisoner transport buses, are exempt from CARB regulations and therefore eligible for CMP funding. Eligible emergency vehicle projects are those in which an older, more polluting emergency vehicle is replaced with a new or used replacement vehicle with an engine meeting the current model year California emission standards. The older, replaced vehicle must be destroyed. Emergency vehicles are eligible for up to 80 percent of the eligible costs as outlined in the program guidelines. 

A fire truck reuse option is also available on a case-by-case basis. The fire truck reuse option allows fire departments to give away the existing old vehicle and destroy another older vehicle in its place.

Additional requirements for emergency vehicle projects can be found at:


This project type involves the repower of an existing, in-use engine with a new, cleaner engine.  The replacement engine must be CARB-certified at or below the emissions levels of 0.10 g/bhp-hr NOx and 0.01 g/bhp-hr PM10.  Repowers may be funded in various applications.  However, due to technological constraints presented with the limited feasibility of newer engines with advanced emissions control equipment fitting into older chassis and maintaining durability, repowers with diesel engines are rare project types for trucks.  Repowers with alternative fuel engines may not have the same technological constraints and may become more prevalent. 

To ensure durability, certain repower projects may require prototype testing.  If the project has been previously completed by the manufacturer, prototype testing is not required.  The prototype testing must comply with the engine manufacturer quality assurance process that is equivalent to an Original Equipment Manufacturer (OEM) package.  In these cases, a prototype vehicle (or vehicles) is thoroughly reviewed and tested to ensure that the installation meets OEM requirements, and the successful prototype installation is then replicated in other vehicles with the same chassis and engine combination.  Per the CMP guidelines, air districts may approve repower projects that meet the OEM quality assurance process described above, subject to the following:

  • Moyer Program funding may not be used for any costs associated with the prototype vehicle or vehicles.
  • Repower contracts may not be executed until the prototype testing specified by the engine manufacturer is successfully completed.
  • Written documentation from the engine manufacturer confirming that the prototype was successful must be maintained in the project file.
  • If the proposed repower has been done previously by the manufacturer on the same chassis/engine configuration, prototype testing is not required. The manufacturer must provide written confirmation that the previous work was performed successfully and met OEM requirements.


This project type involves the replacement of an older, in-use vehicle with a newer, cleaner vehicle.  The replacement engine must be CARB-certified at or below the non-FEL emission level of 0.10 g/bhp-hr NOx and 0.01 g/bhp-hr PM10.  In alignment with South Coast AQMD’s 2016 AQMP, all on-road projects under the CMP must select the optional low-NOx or zero emission technologies for fleet sizes of greater than 10 vehicles.  Fleet size is determined based on the number of vehicles with a GVWR of 14,001 lbs or greater. 

The South Coast AQMD requires that all on-road projects be operated within the South Coast AQMD jurisdiction for at least 75% of the time.  Applicants must clearly demonstrate their compliance status with the applicable CARB regulation (i.e. Statewide Truck & Bus Regulation, Drayage Truck Regulation, Fleet Rule for Public Agencies & Utilities, Transit Bus Regulation, TRU ATCM, etc.) at the time of application submittal.

Please note that if you are an owner of a fleet with 10 or fewer vehicles (greater than 14,000 lbs. GVWR), you may be eligible for funding through the On-Road Voucher Incentive Program (VIP). Please refer to the South Coast AQMD’s VIP Web page to explore funding opportunities for replacement at:

In addition, the following on-road projects will be considered on a case-by-case basis:

  • On-road vehicles with a GVWR between 8,501 and 14,000 pounds,
  • Retrofits that reduce NOx by at least 15 percent; for engines that are certified above 0.01 g/bhp-hr PM, the retrofit must also reduce PM emissions by 85 percent,
  • Zero-emission transport refrigeration units (TRUs)

How to Apply:

Applications are currently open. Please apply on-line here.

Useful Links and Resources:

  • Links to CARB Rules that Affect CMP Eligibility (please check the appropriate website for applicable CARB regulation and compliance dates):

CARB Rules


On-Road Private

Public/Utility Fleets

For additional CMP information on On-Road Heavy-Duty Vehicles, please contact Krystle Martinez at (909) 396-3021 or by email at

Back to Carl Moyer Main Page.

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