Clean Truck Check: Requirements and CARB References

Check vehicle eligibility, registration and CTC-VIS deadlines against current CARB guidance before scheduling heavy-duty emissions testing.

Identify the vehicle and registration

Clean Truck Check applies to specified heavy-duty vehicles operating in California, including some vehicles registered elsewhere. Exemptions matter: CARB lists motorhomes registered outside California as exempt. Establish vehicle type, GVWR, fuel, engine year and registration before applying a general rule. CARB: Clean Truck Check FAQ and exemptions

Confirm test method and due dates

CARB distinguishes OBD testing from smoke-opacity and visual inspection according to the applicable vehicle/engine requirements. Use the engine emissions label rather than assuming the chassis year is the engine year. Due dates are shown in CTC-VIS. CARB: Clean Truck Check testing requirements

Testing frequency has exceptions

Most subject vehicles follow semiannual testing. CARB describes quarterly testing from October 2027 for OBD-equipped vehicles, while qualifying agricultural vehicles and California-registered noncommercial motorhomes remain annual. Confirm classification and the actual account deadlines. CARB: Clean Truck Check testing requirements

Keep Clean Truck Check separate from ACF

Do not present Advanced Clean Fleets purchase obligations as a universal condition of a Clean Truck Check appointment. CARB’s June 2026 guidance distinguishes public-agency obligations and proposed amendments affecting private-fleet provisions; its enforcement notices must also be consulted. Do not rely on a blanket statement that all large private fleets must already have purchased zero-emission trucks. CARB: June 2026 ACF guidance; CARB: enforcement context for high-priority and drayage fleets

If a truck fails

Obtain the actual test result and diagnostic findings. Repair the established cause and complete the required retest or follow-up. An opacity percentage from an unsourced model-year table is not a substitute for the applicable test standard. For Southern California service, contact Torque Edge with vehicle and location details. Ask which charges cover testing, diagnostics, repair and retesting.

Sources and scope

References describe the applications and editions named in each document. For work on a truck, select current service information by engine serial number, reporting controller and calibration. A general guide does not replace those procedures.

• CARB: Clean Truck Check FAQ and exemptions
• CARB: Clean Truck Check testing requirements
• CARB: June 2026 ACF guidance
• CARB: enforcement context for high-priority and drayage fleets