--- title: "Clean Truck Check Testers in Paso Robles, CA (5 listed)" description: "Find 5 CARB-credentialed Clean Truck Check testers in Paso Robles, San Luis Obispo County: 5 offer mobile testing, 1 do smoke opacity tests. Phone numbers…" url: "https://ctcfinder.com/testers/san-luis-obispo-county/paso-robles/" updated: "2026-11-01" publisher: "CTC Finder (independent directory, not affiliated with CARB)" --- # Clean Truck Check testers in Paso Robles, CA 5 testing businesses in Paso Robles (San Luis Obispo County) are on CARB's public Clean Truck Check tester list (5 credentialed testers). 5 offer mobile testing, 1 do smoke opacity tests, 3 test motorhomes. > CTC Finder is an independent directory, not affiliated with CARB. Tester data: CARB Clean Truck Check public tester list, last checked November 1, 2026. Confirm services, hours and prices with the tester. ## Testers in Paso Robles - **[Coops Carb Compliance LLC](https://ctcfinder.com/tester/coops-carb-compliance-llc-paso-robles/)** — 6520 Long Hill Pl, Paso Robles, CA 93446 — (620) 778-2208. Services: mobile testing, OBD testing. - **[D's Diesel N' Off- Road](https://ctcfinder.com/tester/ds-diesel-n-off-road-paso-robles/)** — 6085 Eucalyptus Rd, Paso Robles, CA 93446 — (805) 286-8116. Services: mobile testing, OBD testing, motorhome testing. - **[Dye's Mobile Diesel Smoke Testing](https://ctcfinder.com/tester/dyes-mobile-diesel-smoke-testing-paso-robles/)** — 655 Cripple Creek Rd, Paso Robles, CA 93446 — (805) 835-2893. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing. - **[Kings Oil Tools](https://ctcfinder.com/tester/kings-oil-tools-paso-robles/)** — Paso Robles, CA 93446 — (805) 610-2796. Services: mobile testing, OBD testing. - **[Mid-State Repair & Service](https://ctcfinder.com/tester/mid-state-repair-and-service-paso-robles/)** — 1946 Wood Duck Ln, Paso Robles, CA 93446 — (805) 729-1068. Services: mobile testing, OBD testing, motorhome testing. ## More testers within 20 miles - **[Mtech Unlimited](https://ctcfinder.com/tester/mtech-unlimited-templeton/)** — Templeton, CA 93465 — (805) 550-8744 — 8 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing. - **[Affordable Auto Care](https://ctcfinder.com/tester/affordable-auto-care-atascadero/)** — 4495 Traffic Way, Atascadero, CA 93422 — (805) 258-1495 — 13 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing. - **[Bennett Diesel Repair](https://ctcfinder.com/tester/bennett-diesel-repair-atascadero/)** — 3355 Chico Rd, Atascadero, CA 93422 — (805) 423-6132 — 13 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing. - **[Darrell Dillard](https://ctcfinder.com/tester/darrell-dillard-atascadero/)** — Atascadero, CA 93422 — (805) 674-8110 — 13 mi. Services: mobile testing, OBD testing, motorhome testing. - **[GK's Clean Truck](https://ctcfinder.com/tester/gks-clean-truck-atascadero/)** — 1500 N Ferrocarril Rd, Atascadero, CA 93422 — (805) 538-4991 — 13 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing. - **[Jeff's Auto Works](https://ctcfinder.com/tester/jeffs-auto-works-atascadero/)** — 9000 El Camino Real, Atascadero, CA 93422 — (805) 459-7830 — 13 mi. Services: mobile testing, OBD testing, motorhome testing. - **[Specialized Equipment Repair](https://ctcfinder.com/tester/specialized-equipment-repair-atascadero/)** — 9005 El Camino Real, Atascadero, CA 93422 — (805) 466-1066 — 13 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing. - **[MAFFEIS Automotive](https://ctcfinder.com/tester/maffeis-automotive-morro-bay/)** — 1700 Park St, Morro Bay, CA 93442 — (805) 369-9222 — 18 mi. Services: OBD testing, motorhome testing. ## Cost Typical published prices in California: OBD test $50–$135 per vehicle; smoke opacity test $190–$200. Prices are set by each tester. ## Frequently asked questions ### How many Clean Truck Check testers are in Paso Robles? CTC Finder lists 5 testing businesses in Paso Robles from CARB's public tester list (5 credentialed testers), last checked November 1, 2026. Listing on CARB's list is optional, so the real number can be higher. ### Is there mobile Clean Truck Check testing in Paso Robles? Yes. 5 listed businesses in Paso Robles offer mobile testing, which means the tester comes to your yard. Use the Mobile filter above to see them. ### How much does a Clean Truck Check test cost in Paso Robles? Testers set their own prices. Published prices for an OBD test are usually $50–$135 per vehicle; smoke opacity tests for older trucks often cost more, and mobile testers may add a trip fee. See the [cost guide](https://ctcfinder.com/guide/cost/). ### How often does my truck need a Clean Truck Check test? Most trucks test twice a year, on a schedule tied to the DMV registration expiration date. CARB says OBD trucks move to four tests a year beginning October 2027. California-registered (non-commercial) motorhomes and agricultural vehicles test once a year. See the [deadline guide](https://ctcfinder.com/guide/deadlines-2026-2027/). ## Nearby cities - [Atascadero](https://ctcfinder.com/testers/san-luis-obispo-county/atascadero/) — 6 listings, 13 mi - [San Luis Obispo](https://ctcfinder.com/testers/san-luis-obispo-county/san-luis-obispo/) — 4 listings, 30 mi