Hear from Our Customers
You’re running a tight operation. The last thing you need is a $10,000-per-day fine because someone missed a Clean Truck Check deadline or filed the paperwork wrong. California’s heavy-duty vehicle compliance requirements changed in 2025, and now your 2013 or newer diesel trucks need emissions testing twice a year.
That’s not a suggestion. It’s the law. And CARB doesn’t send reminders before they send penalties.
Here’s what proper CARB diesel compliance actually gets you: no registration blocks at the DMV, no roadside violations during spot checks, and no scrambling when you get a “Notice to Submit to Testing” letter with a 30-day clock. You get certified results submitted directly to the state database by a CARB-credentialed tester. You get documentation that holds up if you’re ever questioned. You get to keep operating without interruption.
This isn’t about checking a box. It’s about protecting your ability to work in California without constantly looking over your shoulder.
We operate in Duarte, right in the heart of the San Gabriel Valley trucking corridor. We’re not a general repair shop that does emissions testing on the side. We’re a CARB-credentialed testing facility that specializes in the exact compliance requirements your 2013 and newer diesel trucks face under California’s CARB HD I/M program.
We handle OBD-based emissions testing for heavy-duty vehicles over 14,000 pounds GVWR. That’s the technical side. The practical side is that we know how to get your trucks tested, documented, and back on the road without the runaround.
Duarte sits along the I-210 and I-605 interchange, which means you’re already dealing with some of the strictest air quality enforcement zones in California. CARB has monitoring stations throughout LA County, and owner-operators and fleet managers in this area get hit with compliance notices regularly. We’re local because your compliance needs are local. When you need semi-annual testing done on time, you need someone who understands the urgency and the regulations.
You schedule your Clean Truck Check appointment based on your compliance deadline. Bring your 2013 or newer diesel truck with a GVWR over 14,000 pounds to our Duarte location. We’ll verify your vehicle qualifies under CARB’s heavy-duty regulations before we start.
The actual test uses OBD diagnostics to check your emissions system. We’re looking at your onboard computer data, not putting a probe in your tailpipe like older smog tests. The system checks for fault codes, readiness monitors, and emissions performance. If everything passes, you’re done. If something flags, we’ll tell you exactly what needs attention before you can retest.
Once you pass, we submit your results directly to CARB’s Clean Truck Check database. You’ll get documentation showing your test date, results, and next compliance deadline. That record stays in the state system, so your registration stays clear and you’ve got proof if you’re ever stopped for a roadside inspection.
You need this done twice a year starting in 2025. Some trucks will need it four times a year by 2027 depending on your vehicle’s age and use. We’ll let you know where your truck falls and when you need to come back. No surprises, no missed deadlines, no penalties you didn’t see coming.
Ready to get started?
You get a CARB-credentialed tester who’s certified to perform heavy-duty vehicle compliance testing under California’s HD I/M program. That credential matters because only certified testers can submit valid results to the state database. A test from anyone else doesn’t count.
You get OBD emissions testing using CARB-approved diagnostic equipment. We’re checking your truck’s emissions control systems the way the state requires, not running some generic scan tool and calling it good. The equipment we use meets CARB’s technical specifications for 2013 and newer diesel engines.
You get proper documentation and database submission. Your results go into CARB’s system within the required timeframe, which keeps your DMV registration active and your compliance record clean. You’ll receive a certificate showing your test date, pass status, and next deadline.
Duarte’s location puts you near major freight routes through LA County and the Inland Empire. If you’re running trucks through Southern California, you’re operating in one of the most heavily monitored air quality regions in the country. CARB’s enforcement isn’t theoretical here. It’s active, it’s consistent, and it’s expensive if you’re caught non-compliant. Our testing keeps you on the right side of that enforcement without the drama.
Your truck needs Clean Truck Check testing if it’s model year 2013 or newer, has a gross vehicle weight rating over 14,000 pounds, and operates in California. This includes semi-trucks, heavy-duty pickups with diesel engines, box trucks, dump trucks, and diesel motorhomes that meet the weight requirement.
The 2013 cutoff isn’t random. That’s when federal regulations required OBD systems on heavy-duty diesel engines, which is what CARB’s testing program uses to check emissions performance. Older trucks fall under different rules. Lighter trucks under 14,000 pounds aren’t part of this program either.
If you’re not sure whether your truck qualifies, check the door jamb sticker for the GVWR and your registration for the model year. Both have to meet the threshold. Out-of-state trucks operating in California need testing too if they’re registered here or spend significant time in the state. CARB doesn’t care where you bought the truck. They care where it operates.
You need Clean Truck Check testing twice a year starting in 2025. That’s semi-annual testing, roughly every six months. CARB sets your specific deadlines based on your vehicle identification number and when you first register for testing.
Some trucks will move to quarterly testing by 2027 depending on the vehicle’s model year and how it’s used. CARB’s phasing this in gradually, but the baseline right now is twice yearly for all qualifying trucks. Miss a deadline and your registration gets flagged. Keep missing it and you’re looking at fines that start at $300 and climb to $10,000 per day per vehicle.
Your test results include your next compliance date. Write it down. Set a reminder. Don’t assume you’ll get a notice from the state because you probably won’t. CARB expects you to track your own deadlines. If you’re running multiple trucks, you’re managing multiple test schedules. That’s why fleet operators usually batch their testing or set up recurring appointments. It’s easier than trying to remember six different deadlines across six different trucks.
If your truck fails, you’ll get a report showing exactly which emissions monitors or fault codes caused the failure. You’ll need to get those issues repaired before you can retest. CARB gives you a window to fix the problem and come back, but that window isn’t unlimited.
Common failure points include check engine lights that haven’t been cleared, emissions system components that aren’t functioning correctly, or readiness monitors that show “not ready” because the system hasn’t completed its self-checks. Sometimes it’s a simple fix like resetting a code after a repair. Sometimes it’s a bigger issue like a failed diesel particulate filter or EGR system.
You can’t just ignore a failed test. Your truck won’t pass registration renewal until you pass emissions testing, and CARB can issue penalties if you keep operating a vehicle that’s failed and hasn’t been retested. Get the repairs done, bring it back, and retest. If you’re worried your truck might fail, some shops offer pre-testing diagnostics to catch problems before the official test. That’s not a bad idea if your check engine light is on or you’ve been having emissions-related issues.
Yes. Clean Truck Check is a separate program from regular smog checks. Even if your truck gets tested under another program, you still need Clean Truck Check if it’s 2013 or newer and over 14,000 pounds GVWR.
Regular smog checks cover passenger vehicles and lighter trucks. Clean Truck Check specifically targets heavy-duty diesel vehicles because they contribute disproportionately to air pollution. CARB estimates heavy-duty vehicles make up only 3% of California’s vehicles but produce over half of the smog-causing emissions. That’s why the state created a dedicated testing program with stricter requirements.
The testing process is different too. Clean Truck Check uses OBD diagnostics and checks specific emissions monitors that don’t exist on lighter vehicles. You can’t substitute one test for the other. If your truck falls under Clean Truck Check requirements, that’s the test you need. Period. Don’t let anyone tell you a regular smog check will cover it. It won’t, and you’ll still be out of compliance.
Testing costs vary depending on the facility and whether you’re getting mobile testing or coming to a fixed location. You’re typically looking at somewhere between $75 and $150 per test for standard service at a testing facility in the Duarte area.
That might sound steep when you’re paying it twice a year per truck, but compare it to the alternative. A single compliance violation starts at $300. If CARB decides you’ve been operating non-compliant for a while, fines jump to $10,000 per day per vehicle. One missed test that turns into a penalty wipes out years of testing costs in a single citation.
Mobile testing services charge more because they come to you, which saves you downtime but adds to the price. Some fleet operators find that worth it when they’re testing multiple trucks. Solo owner-operators usually come to the shop because it’s cheaper. Either way, the test itself is the same. You’re paying for CARB-credentialed testing, proper documentation, and database submission. That’s not optional, and it’s not negotiable. Budget for it the same way you budget for fuel and insurance, because it’s just as mandatory.
No. You need a CARB-credentialed tester who’s specifically certified for heavy-duty vehicle emissions testing. Not every smog shop has that credential, and not every shop has the equipment to test trucks over 14,000 pounds.
CARB maintains a list of credentialed testers, but that list isn’t as long as you’d think. Most regular smog shops only handle passenger vehicles. Heavy-duty testing requires different diagnostic tools, different training, and different certification. If you show up somewhere that’s not credentialed, they can’t help you. Your test won’t count even if they run it.
Location matters for another reason too. If you’re based in Duarte or running routes through the San Gabriel Valley, you want a testing facility that understands local enforcement patterns and can get you in quickly when you’re up against a deadline. CARB’s enforcement is heaviest in Southern California, especially LA County and the Inland Empire. Testing facilities in these areas see more trucks and handle more compliance issues than shops in rural counties. That experience makes a difference when you’ve got a problem that needs solving fast.
Local Resources
Useful Links
Other Services we provide in Duarte
