---
title: "Clean Truck Check Testers in Marin County, CA (4)"
description: "4 CARB-credentialed Clean Truck Check testers in Marin County, California, across 4 cities. 3 offer mobile testing. Search by city, see phone numbers and…"
url: "https://ctcfinder.com/testers/marin-county/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Clean Truck Check testers in Marin County, California

4 testing businesses in 4 cities; 3 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.


## Belvedere Tiburon

- **[Redwood Engineering](https://ctcfinder.com/tester/redwood-engineering-belvedere-tiburon/)** — Belvedere Tiburon, CA 94920 — (510) 314-9605. Services: mobile testing, OBD testing, motorhome testing.

## Novato

- **[Hamilton's Smog](https://ctcfinder.com/tester/hamiltons-smog-novato/)** — 1032 1st St, Novato, CA 94945 — (415) 378-3252. Services: OBD testing, motorhome testing.

## San Rafael

- **[Emeraldauto](https://ctcfinder.com/tester/emeraldauto-san-rafael/)** — 20 Bridgegate Dr, San Rafael, CA 94903 — (415) 871-4148. Services: mobile testing, OBD testing, motorhome testing.

## Tomales

- **[Mobile HD services](https://ctcfinder.com/tester/mobile-hd-services-tomales/)** — 25300 Highway 1, Tomales, CA 94971 — (707) 326-6965. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing.


## Frequently asked questions

### How many Clean Truck Check testers are in Marin County?

CTC Finder lists 4 testing businesses in Marin County 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 Marin County?

Yes. 3 listed businesses in Marin County 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 Marin County?

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/).