California’s Clean Truck Check now hits almost every diesel truck over 14,000 lb that runs in the state — including out-of-state fleets. Miss it and your registration gets blocked. Enter a truck and X3 tells you what test you owe, when it’s due, and your risk.
Free · instant · X3 analysis of CARB rules — verify at CARB
The money isn’t in running the test — it’s in not losing your registration, eating a fine, or getting turned around at the California line. Most owners have no idea what applies to their trucks until a notice shows up.
If your truck operates in California — even once — Clean Truck Check can apply. Fleets based in Texas, Ohio, Georgia get caught off guard because they assume it’s a “California problem.” It’s a your-truck-in-California problem.
2013-and-newer diesel (2018+ alt-fuel) get an OBD scan; 2012-and-older diesel get a smoke-opacity test plus a visual. Twice a year now, four times a year from October 2027. Miss a window and the registration block follows.
The Advanced Clean Trucks / Advanced Clean Fleets purchase mandates were revoked in 2025, so nobody’s forcing you to buy an electric truck. But Clean Truck Check — the testing program with the registration teeth — is very much alive. We track what’s real, not the headlines.
A blocked registration parks the truck. We make sure that never happens.
X3 figures out what each truck owes, when it’s due, and what it’ll cost — then keeps watch so nothing lapses.
VIN or just fuel, engine year, GVWR and where you run. X3 determines Clean Truck Check applicability for each unit — in-state and out-of-state.
Which test (OBD vs opacity), how often, the annual fee, and each truck’s status: compliant, due soon, or registration-block risk. Plus a fleet compliance score.
Deadline alerts before anything lapses, and an AI assistant for “can my 2012 truck run in California?” — answered against the current rules, with the CARB source.
Self-serve, AI-run. CARB fees and the test itself are paid separately. Pricing illustrative.
One or two trucks, never lapsed.
Whole fleet, one dashboard. +$3/truck over 25.
Before you buy a used truck.
A team of specialized AI agents — each one a callable unit of compliance intelligence, grounded in the X3 DOT Skills corpus and verified 49 CFR.
Powered by the X3 DOT Skills corpus. Every answer quotes the actual regulation — never made up.
Not one chatbot — a crew. 7 specialists, each owning one part of the job, every answer grounded in the CFR and cited to the rule.
Answers any Clean Truck Check / CARB emissions question.
Keeps your CARB Clean Truck Check registration and status current.
Guides OBD and opacity/smoke testing requirements and timing.
Tracks CTC testing deadlines and fees before they hit.
Prepares and files your compliance reporting.
Checks which trucks are subject and which are exempt.
Explains federal heavy-duty emissions context alongside CARB.
Every plan includes the full AI team and every tool — you only pay by how many trucks you run. Every plan starts with a 7-day free trial.
$299 base covers 30 trucks; each additional truck is $10/mo.
Start 7-day trialPrices in USD/month. Over 30 trucks billed at $299 base + $10 per additional truck. 100+ trucks — contact sales for a custom plan. Compliance assistance grounded in the CFR — not legal advice.