CARB Compliance for Commercial Trucks 2026
The California Air Resources Board (CARB) enforces some of the most stringent heavy-duty diesel truck regulations in the United States. Any commercial truck operating in California — regardless of registration state — must comply with CARB rules. Key programs include the Clean Truck Check, a biennial opacity inspection for diesel trucks over 14,000 lbs GVWR; the Drayage Truck Rule, which mandates zero-emission vehicles for trucks serving California ports and intermodal railyards; the Advanced Clean Trucks (ACT) rule governing manufacturer ZEV sales quotas; and the Heavy-Duty Vehicle Inspection Program (HDVIP), CARB's roadside enforcement program. All qualifying trucks must be registered in TRUCRS (Truck, Bus, and Off-Road Clean Air Reporting System) and kept current. Non-compliance can result in fines of $1,000 or more per day per vehicle, mandatory Notice to Correct orders, and denial of entry at California ports and railyards.

Clean Truck Check
The Clean Truck Check (CTC) program — formerly known as the Periodic Smoke Inspection Program — requires all heavy-duty diesel trucks over 14,000 lbs GVWR operating in California to pass a biennial (every two years) smoke opacity test. The test measures visible exhaust smoke during acceleration; excessive opacity indicates a poorly maintained or malfunctioning diesel engine.

Every 2 years
Frequency
Biennial inspection required
> 14,000 lbs
GVWR Threshold
Diesel engines only
Up to $1,000
Daily Fine
Per vehicle, per day
All vehicles subject to Clean Truck Check must be registered in TRUCRS. Inspection results are logged against the vehicle's record. Out-of-state trucks are not exempt — if your vehicle operates in California, it must be enrolled in TRUCRS and inspected on the two-year cycle.

Drayage Truck Rule
The CARB Drayage Truck Regulation applies to trucks that haul cargo to or from California seaports and intermodal railyards. Drayage trucks must be registered in the CARB TRUCRS system and meet zero-emission vehicle (ZEV) requirements on a phased timeline.

2023
New drayage truck registrations must be zero-emission

2024
All new drayage registrations at CA ports/railyards must be ZEV

2035
All drayage trucks operating at CA ports and railyards must be zero-emission