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If you’re running a 2013 or newer heavy-duty truck in California, you already know the state doesn’t mess around. Miss your Clean Truck Check deadline and you’re looking at registration holds, fines that can hit $10,000 per vehicle per day, and trucks sitting idle when they should be making you money.
You need testing done by someone who actually knows what they’re doing. Not someone who treats your semi truck like a passenger car or wastes your time with guesswork.
We handle CARB HD I/M testing for trucks over 14,000 pounds GVWR with the OBD systems that 2013+ models require. We’re CARB credentialed, we use certified equipment, and we know the deadlines are every six months—not once a year like a regular smog check. You get in, we run the test, and you get back on the road. That’s it.
We’re not new to Santa Clarita, and we’re not new to working with commercial operators who can’t afford to sit around waiting. We’ve built our reputation on understanding what fleet owners and owner-operators actually need: accurate testing, no runaround, and someone who knows the difference between a smog test for your Honda and CARB clean truck check requirements for a Class 7 diesel.
Santa Clarita sits right in the path of major freight routes. That means we see plenty of trucks registered out of state that still need California compliance testing. We also work with local construction outfits, utility fleets, and independent haulers who depend on their trucks to stay operational.
If your truck qualifies—2013 or newer, over 14,000 GVWR—we’ll get you tested and reported to CARB so you can move on with your day.
You bring in your 2013 or newer heavy-duty truck. We plug into the OBD system using CARB-certified test equipment—this isn’t a visual inspection or a sniffer test. The system pulls data directly from your truck’s onboard diagnostics to check emissions performance.
The test itself takes a few minutes if everything’s running clean. If your truck passes, we submit the results directly to CARB and you get documentation showing you’re compliant. You can submit a passing test up to 90 days before your deadline, so if you’ve got a window where the truck’s already down for maintenance, that’s a smart time to knock it out.
If something comes back flagged, we’ll tell you what the system found. You’ll need to get the issue fixed before retesting, but at least you’ll know exactly what you’re dealing with instead of guessing. Once it’s repaired and passes, you’re good for the next six months.
The state charges $31.18 per test as of 2025, and that goes to CARB—not us. Our job is to run the test correctly and get your results filed so you don’t end up with a registration problem later.
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This isn’t a standard smog check. It’s a specialized CARB clean truck check that only applies to heavy-duty diesel and diesel hybrid trucks with 2013 or newer engines and a gross vehicle weight rating of 14,000 pounds or more. If your truck doesn’t meet those specs, this isn’t the service you need.
We’re a CARB credentialed testing facility, which means we’ve completed the state’s training, passed the exam, and use only approved OBD testing devices. That’s not optional—it’s the only way your test results will be accepted by the state.
Santa Clarita’s location makes it a natural stop for fleets moving through the region, and we see a mix of local commercial trucks and out-of-state operators who need California compliance. The testing requirement kicked in October 2024, and deadlines started January 2025. If you’re not sure when yours is due, it’s based on your VIN and happens twice a year.
You also need to know this is ongoing. It’s not a one-time thing. Every six months, your truck needs a passing test to stay registered and legal in California. Miss it and the DMV can freeze your registration until you’re compliant.
If your truck is model year 2013 or newer and weighs over 14,000 pounds GVWR, you need a Clean Truck Check—not a regular smog check. This is a completely different test that uses your truck’s OBD system and gets reported to CARB, not the Bureau of Automotive Repair.
Regular smog checks are for passenger vehicles and lighter trucks. They don’t meet the requirements for heavy-duty compliance. If you take your semi truck to a regular smog shop, they’re probably going to turn you away or give you a test that won’t count.
The easiest way to know for sure is to check your registration notice. If it mentions HD I/M or Clean Truck Check, that’s what you need. If you’re still not sure, call us and we’ll walk you through it based on your truck’s year and weight rating.
Every six months. California requires CARB emissions testing twice a year for trucks that fall under the Clean Truck Check program. Your specific deadline is tied to your VIN, so it’s not the same for everyone.
You’ll get a notice from the DMV telling you when your test is due. You can submit a passing test up to 90 days before that deadline, which gives you some flexibility if you want to time it with other maintenance or during a slower season.
Miss your deadline and the DMV can put a hold on your registration. That means your truck can’t legally operate in California until you get compliant. It also opens you up to fines that can add up fast—up to $10,000 per vehicle per day in some cases. It’s not worth the risk.
If your truck fails, the test results will show what triggered the failure—usually an emissions system issue flagged by the OBD system. You’ll need to get that problem repaired before you can retest and pass.
We’ll give you documentation that shows exactly what failed so you or your mechanic knows what to fix. Once the repair is done, you come back for another test. If it passes, we submit the results to CARB and you’re compliant.
The $31.18 state fee applies each time you test, so a failure does mean you’re paying that fee twice. But it’s still cheaper than operating with a failed test and risking registration holds or penalties. The key is addressing the issue quickly so your truck isn’t sitting idle any longer than it has to.
Yes. If your truck is registered outside California but operates in the state, you still need to comply with CARB’s Clean Truck Check requirements. It doesn’t matter where your plates are from—if you’re running a 2013+ heavy-duty truck in California, the rule applies.
We test out-of-state trucks regularly, especially since Santa Clarita is along major freight corridors. The process is the same: we run the OBD test, submit the results to CARB, and you get your documentation.
Make sure you understand your compliance schedule, because it’s based on when your truck operates in California, not when it’s registered elsewhere. If you’re crossing state lines frequently, it’s worth getting ahead of the deadline so you’re not scrambling to find a testing location at the last minute.
The actual OBD test takes just a few minutes once we’re plugged into your truck’s system. If everything’s running clean and there are no flags, you’re looking at a quick in-and-out appointment.
The total time depends on whether there’s a line and how fast your truck’s system communicates with the test equipment. Most trucks with 2013+ OBD systems are pretty straightforward. We’re not doing a visual inspection or putting your truck on a dyno—this is a data pull from the onboard diagnostics.
If your truck fails, that adds time because you’ll need to get it repaired and come back for a retest. But assuming your emissions system is in good shape, this shouldn’t eat up your whole afternoon. We know your truck makes money when it’s moving, not when it’s parked at a test station.
CARB HD I/M testing—also called Clean Truck Check—is specifically for 2013 and newer heavy-duty trucks over 14,000 GVWR. It uses OBD data to check emissions performance and gets reported directly to the California Air Resources Board. It’s required every six months.
A diesel smog check, on the other hand, usually refers to older testing methods like opacity tests or visual inspections for trucks that don’t have OBD systems. Those tests are different, use different equipment, and are handled under different regulations.
If your truck is 2013 or newer with an OBD system, you need the Clean Truck Check. Older trucks may fall under different rules. The state has been tightening emissions requirements across the board, so it’s worth confirming exactly what your truck needs based on its model year and weight. We can help you figure that out if you’re not sure.
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