Clean Truck Check vs. Traditional Smog Check — What’s the Difference?

Title: Clean Truck Check vs Smog Check: What’s the Difference? Meta Description: Not sure how Clean Truck Check compares to a traditional smog check? Learn the key differences here.

Not Your Typical Smog Check

If you’re used to getting your diesel truck smogged every few years at a test-only station, get ready for a big change. The Clean Truck Check isn’t just a stricter version of your regular smog inspection — it’s an entirely new regulatory framework built specifically for heavy-duty diesel vehicles.

Let’s break it down.


Smog Check (Old System)

  • Occurred every 2 years
  • Often for passenger and light-duty vehicles
  • Simple plug-in or tailpipe test
  • Didn’t always apply to commercial or diesel vehicles

Clean Truck Check (New CARB Law)

  • Applies to ALL trucks over 14,000 lbs GVWR
  • Includes out-of-state and fleet vehicles
  • Requires semi-annual emissions testing
  • Mandatory compliance with CARB standards
  • Enforced with remote sensing tech, DMV data, and fines

Why the Shift?

CARB determined that heavy-duty vehicles are among the top contributors to smog and poor air quality in California. This new regulation targets emissions from commercial diesel engines, not just private cars.


What Vehicles Are Affected?

  • Class 4-8 trucks
  • Diesel box trucks and delivery vans
  • Flatbeds, tow trucks, utility vehicles
  • Buses and charter vehicles
  • Out-of-state diesel trucks driving in California

What’s Required Now?

  • Bi-annual emissions tests using CARB-certified equipment
  • Digital submissions to CARB’s tracking system
  • Documentation for fleet management and DMV

How APDCarb Makes It Easy

Whether you’re switching over from a traditional smog check schedule or navigating Clean Truck Check requirements for the first time, we provide:

  • Mobile testing
  • Fast compliance documentation
  • Support for fleets and owner-operators

📞 Call to Action

Still doing smog checks the old way? Time to upgrade.
Call 619-567-9010 or book your Clean Truck Check here