CARB Clean Truck Check: What Every California Fleet Needs to Know

If you run a diesel truck over 14,000 lbs on California roads, the Clean Truck Check applies to you — and the penalties for ignoring it are steep enough to park your business.

What It Is

The Clean Truck Check is California's heavy-duty vehicle emissions compliance program. It requires periodic emissions testing for nearly all diesel and alternative-fuel vehicles over 14,000 lbs GVWR that operate on California public roads — including trucks registered out of state.

The Penalties Are Not Small

• Up to $10,000 per vehicle, per day for non-compliance.
• Trucks can be put out of service by enforcement — meaning that load stops moving.
• Out-of-state trucks can be restricted from operating in California entirely.

The Testing Schedule Is Tightening

The compliance cadence has been ramping up, with testing required multiple times per year for most vehicles and the frequency increasing over the next few years. The practical takeaway: this isn't a one-and-done. Build it into your maintenance rhythm so you're never scrambling after a notice arrives.

How To Stay Ahead Of It

• Test before you're forced to. A scheduled test is cheap; a fine or a parked truck is not.
• Use a shop that can also fix a failure. If your truck fails, you don't want to be sent somewhere else — you want it diagnosed and repaired on the spot, then re-tested.
• Bundle it with maintenance. Pairing your Clean Truck Check with regular PM service means one visit, not two.

All Mechanical performs Clean Truck Check testing on-site across the Bay Area — and because we're a full diesel repair operation, we can repair the cause of a failure right there and re-test. See how our Clean Truck Check service works.