Your diesel trucks need an emissions test. We come to your yard and do it.
California’s Clean Truck Check applies to almost every non-gasoline vehicle over 14,000 lbs on the road here. We’re a mobile testing service based in South San Francisco. Your trucks stay on your lot and your drivers keep their shift.
OBD compliance testing for 2013 and newer diesel engines. Results submitted directly to CARB.
What California requires of every subject vehicle
Clean Truck Check is CARB’s Heavy-Duty Inspection and Maintenance program. It’s in active enforcement, and compliance has three parts.
Report the vehicle
Every subject vehicle has to be entered in CARB’s Clean Truck Check Vehicle Inspection System, known as CTC-VIS.
Pay the annual fee
A compliance fee is owed each year for every vehicle in the system. It was $32.13 as of January 1, 2026.
Pass a periodic test
Emissions testing on a recurring schedule, submitted to CARB by a credentialed tester. That’s the part we handle.
It covers more trucks than most people expect
- Class 4 and up, not just tractors. F-450 and F-550, Isuzu NPR-HD, Hino 195 and 268, Freightliner M2, Ram 4500 and 5500.
- Vocational equipment counts. Dumps, roll-offs, box trucks, buses, boom trucks, vac trucks, service bodies, car haulers.
- Out-of-state plates are not exempt. If the vehicle operates on California roads, it’s subject to the program.
- Low-use and seasonal units count unless they meet a specific exemption in the regulation.
Non-compliance can trigger DMV registration holds and penalties.
What happens if a vehicle isn’t compliant
Enforcement doesn’t depend on anyone pulling you over. CARB uses roadside and remote emissions monitoring alongside the DMV registration system.
Most fleets find out the hard way, at renewal, when a truck they need that week can’t be registered.
- DMV registration holdA non-compliant vehicle can’t be registered. A truck that can’t be registered can’t legally work.
- Civil penaltiesAssessed per vehicle. The cost of a missed test is many times the cost of the test.
- No quiet way throughRoadside and remote monitoring identify vehicles with emissions faults whether or not anyone reports them.
How we work, and what it costs
- We come to you. Testing happens in your yard, on your schedule. No one drives a truck across town and waits at a shop.
- OBD scan for 2013 and newer diesel engines. We connect, verify the readiness monitors are set, and run the test.
- We file the result. Passing tests go directly to CARB’s system, so nothing is left sitting on your desk.
- One truck or twenty. We’ll come out for a single unit, and we’ll block out a morning for a whole fleet.
- Scheduling that fits a working yard. Before the trucks roll out, after they come back, or on a weekend.
We currently provide OBD testing only. If your fleet includes pre-2013 engines that need smoke opacity testing, tell us the split and we’ll point you to someone who can cover those.
| 1–2 vehicles | $150/ea |
|---|---|
| 3–6 vehicles | $125/ea |
| 7+ vehicles | $95/ea |
No trip charge and no fuel surcharge, wherever you are. The price on this list is the price. Tiers apply to vehicles tested during the same visit.
Where we test
Based in South San Francisco. We work the whole Bay Area and we travel — if you run diesel over 14,000 lbs and you’re not on this list, ask anyway.
San Francisco & North Peninsula
Our home ground. Same-week service is normal here, often same-day.
South Peninsula & South Bay
Coastside, north and south
East Bay
North Bay
And beyond
We never charge a travel fee, wherever you are. What we ask instead is three units minimum outside the North Peninsula, and some lead time, since we run those areas on set days. Only have one or two? Combine with a neighbouring yard and we’ll do both in one visit. Further out than the Bay Area? Tell us the count and where you are — for a big enough fleet we’ll come to you.
Request a visit
Send us your fleet details and we’ll confirm a time, usually within one business day. We’ll tell you up front how many of your units we can test and what it’ll cost.
- We confirm the time with you rather than dropping you into a slot that doesn’t work.
- We check engine model years before the visit, so there are no surprises in the yard.
- No obligation. If we’re not the right fit for your fleet, we’ll say so.
Questions fleet owners ask us
How often does my fleet need to be tested?
Testing is on a recurring schedule set by CARB, and the required frequency has been changing as the program phases in. Rather than quote a number that may be out of date by the time you read it, call us with your vehicle list and we’ll tell you where each unit stands and what’s current.
My trucks are registered in another state. Am I exempt?
No. Clean Truck Check applies to vehicles operating on California public roads regardless of where they’re registered. If your trucks come into California, they’re subject to the program.
What is OBD testing and why does the engine year matter?
Heavy-duty engines from the 2013 model year forward have on-board diagnostic systems. Testing those vehicles means connecting to that system, confirming the readiness monitors are set, and transmitting the result to CARB. Engines older than that don’t have the system, so they’re tested with a smoke opacity test instead, which is a different procedure and different equipment.
Do you test pre-2013 engines?
Not currently. We do OBD testing only. If your fleet is mixed, tell us the split when you get in touch and we’ll be straight with you about what we can cover and who can handle the rest.
What does the visit actually look like?
We come to your yard at the agreed time. Each truck needs to be accessible and the engine needs to run during the test. A single unit takes a few minutes. For a larger fleet, line the trucks up and we’ll work straight through. You get the results, and CARB gets them too.
What if a truck fails?
A failure means the vehicle has an emissions-related fault that needs repair before it can pass. We’ll tell you what the system reported so your shop knows where to start, and we’ll come back and retest once the repair is done.
What does it cost?
$150 per vehicle for one or two, $125 each for three to six, and $95 each for seven or more tested during the same visit. There are no travel fees and no fuel surcharge, anywhere we go — the per-vehicle rate is the whole price. If your fleet sits near a tier break, tell us your count and we will quote it before we come out.
How far do you travel?
The whole Bay Area, and we never add a travel fee wherever it is. San Francisco and the North Peninsula are our home ground, usually same week. Beyond that — the South Bay, the coast, the East Bay and the North Bay — we run on set days and ask for three units minimum, which is how we keep the drive free rather than billing you for it. Further out than the Bay Area? Tell us the count and where you are and we will work it out.
Do I have to bring my trucks somewhere?
No. That’s the whole point of what we do. We bring the equipment to your yard so your vehicles stay where they are and your drivers stay on the job.