Everything you need to know about CARB's Clean Truck Check program and what to expect from your inspection.
What is a CARB Clean Truck Check?
The Clean Truck Check (CTC) is California's inspection and maintenance program for heavy-duty diesel vehicles. Required by the California Air Resources Board, it ensures trucks meet current emissions standards to reduce air pollution across the state.
Does my truck need to be tested?
If you operate a diesel truck or bus with a gross vehicle weight rating (GVWR) over 14,000 lbs on California roads, you are likely subject to the CTC regulation. Most vehicles model year 2013 and newer with applicable engines are required to comply.
How often do I need an inspection?
Inspection frequency depends on your vehicle's model year and engine. Inspections are required every 6 months. CARB's database tracks compliance records, so staying current protects you from citations and keeps your trucks on the road.
What happens if I fail?
If your truck doesn't pass, we'll document exactly what needs to be repaired. This is where our $60 Pre-Check pays off — we identify issues before your official test so you can fix them first, pass with confidence, and protect your compliance record.
What does the inspection check for?
The Clean Truck Check verifies that your vehicle's emissions control systems — including the diesel particulate filter (DPF), exhaust gas recirculation (EGR), and selective catalytic reduction (SCR) — are functioning correctly and haven't been tampered with or removed.
Do you offer opacity testing?
No — we specialize exclusively in Clean Truck Check inspections for 2013 model year engines and newer. We do not perform opacity (smoke) testing. Not sure if your truck qualifies? Call us before booking and we'll tell you right away.
What are the fines for non-compliance?
CARB enforcement penalties start at $1,000 and can increase significantly for repeat or ongoing violations. Vehicles found non-compliant may also be placed out of service — meaning lost revenue on top of fines. Staying current is always the cheaper option.
How long does an inspection take?
A typical Clean Truck Check inspection takes just 15–20 minutes per vehicle. For fleet visits, we work efficiently to get through your trucks quickly. Since we come to your location, your drivers stay on-site and productive the entire time.
