510-589-8108|Serving All of California

What We Do

On-Site Diesel Emissions Testing

We bring certified testing equipment directly to your location. No towing, no scheduling conflicts, no lost work time.

Every Diesel Vehicle. Every Location.

California's CARB regulations apply to virtually every diesel-powered vehicle on the road. Whether you operate a single RV or a fleet of 50 box trucks, staying compliant is non-negotiable — and we make it as painless as possible.

RVs & Motorhomes

Tested where you store or park them

RVs & Motorhomes

Full-size Class A, B, and C motorhomes — including diesel pushers — require regular emissions testing under California law.

What to Expect

  • Fast and accurate testing process
  • We test at your storage facility, campground, or home
  • Same-day compliance update to your CTC account and DMV
  • Applicable to all diesel-powered motorhomes
Tow Trucks

Keep your fleet on the road

Tow Trucks

Tow trucks are working vehicles — every hour off the road is revenue lost. We schedule around your dispatch calendar and test at your yard.

What to Expect

  • Testing at your yard or dispatch location
  • Flexible scheduling around your operations
  • All tow truck classes and configurations
  • Same-day compliance documentation
Box Trucks

Fleet testing at your warehouse or yard

Box Trucks

Delivery fleets, freight operators, and moving companies rely on box trucks every day. We test your entire fleet on-site.

What to Expect

  • On-site testing at your warehouse or yard
  • Multi-vehicle fleet testing available
  • Minimal disruption to delivery schedules
  • Documentation ready same day
All Diesel Trucks

If it runs on diesel, we test it

All Diesel Trucks

Beyond RVs and tow trucks, we test any diesel-powered commercial vehicle — dump trucks, flatbeds, refrigerated trucks, utility vehicles, and more.

What to Expect

  • Any diesel-powered commercial vehicle
  • Dump trucks, flatbeds, refrigerated units, and more
  • Testing at your job site, yard, or facility
  • Same-day compliance documentation

OBD Compliance

What OBD Testing Covers

The electronic test for modern diesel fleets

CARB's Clean Truck Check program requires all 2013 and newer heavy-duty diesel engines with a GVWR over 14,000 pounds to submit periodic OBD (On-Board Diagnostics) compliance tests. The test verifies three things: no active emissions-related trouble codes, completed readiness monitors, and clean communication with the engine's emissions control module.

When your truck passes, the result transmits electronically to CARB in near-real-time. CARB then releases the compliance record to DMV the same business day. If you had a registration hold, it typically lifts within hours.

Vehicles we test with OBD

  • Class 7 and Class 8 heavy-duty trucks (2013+)
  • School buses, motor coaches, and transit buses (2013+)
  • Heavy-duty motorhomes and RVs over 14,000 lbs GVWR
  • Refrigerated delivery trucks, dump trucks, and service fleets
  • Agricultural and utility heavy-duty trucks

How the test runs on-site

  1. 1Arrival and check-in. Our credentialed tester confirms your vehicle(s), VINs, and your CARB Clean Truck Check account.
  2. 2Scan tool connection. Certified OBD scanner connects to the truck's diagnostic port. The engine is run briefly to verify communication.
  3. 3Data capture. The scanner records MIL status, DTCs, readiness monitors, and compliance data.
  4. 4Upload to CARB. Results submit electronically while we are still on-site. You receive a digital confirmation.
  5. 5Invoice and depart. Cards, e-check, or cash accepted. We can test the next vehicle or head to the next stop.

The Process

What Happens During a Test

01

Visual Inspection

We check the vehicle's engine, exhaust system, and emissions components before testing begins.

02

Emissions Measurement

Our certified equipment measures exhaust output against California CARB standards.

03

Documentation

Pass or fail, you receive a detailed report on the spot. Passing vehicles get their compliance certificate immediately.

Ready to Schedule?

Call or text to book your on-site test. We work around your schedule.

Call Now: 510-589-8108
Mobile Diesel Testing

California CARB-compliant diesel emissions testing — brought directly to your fleet yard, warehouse, or job site.

Service Area

Northern California
Southern California
Central California

We come to your location — fleet yards, warehouses, storage facilities, and job sites throughout California.

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California diesel emissions testing — statewide service