---
title: "Freedom smog — Clean Truck Check, Riverbank, CA | CTC Finder"
description: "Freedom smog in Riverbank, CA is on CARB's Clean Truck Check tester list. Offers mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome…"
url: "https://ctcfinder.com/tester/freedom-smog-riverbank/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Freedom smog

Clean Truck Check tester in Riverbank, CA (Stanislaus County).

> 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.

| Field | Value |
|---|---|
| Location | 2660 Patterson Rd, Riverbank, CA 95367 |
| County | Stanislaus County |
| Phone | (209) 622-9156 |
| Mobile testing | Yes |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | Yes |
| Motorhomes | Yes |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks Freedom smog can test

| Your vehicle | Test required | This tester |
|---|---|---|
| Diesel, model year 2013 or newer | OBD scan | Yes |
| Alternative fuel (natural gas, propane), 2018 or newer | OBD scan | Yes |
| Diesel, model year 2012 or older (no OBD) | Smoke opacity test (SAE J1667) plus visual inspection | Yes |
| California-registered motorhome | Same test as above by engine year, once a year | Yes |

## Clean Truck Check testers in Stanislaus County

Freedom smog is one of 53 testing businesses in Stanislaus County on CARB's public tester list. 47 of them offer mobile testing and 22 do smoke opacity tests.

## When your truck is due

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/). You can test up to 90 days before a deadline. Free email reminders: https://ctcfinder.com/reminders/

## Frequently asked questions

### Does Freedom smog offer mobile Clean Truck Check testing?

Yes. Freedom smog says on CARB's tester list that it offers mobile testing, so it can come to your yard or job site. Ask about a trip fee when you call.

### Can Freedom smog test a 2012 or older diesel truck?

Yes. Freedom smog lists smoke opacity testing, the test CARB requires for diesel trucks of model year 2012 and older (no OBD). See [OBD vs smoke opacity](https://ctcfinder.com/guide/obd-vs-smoke-opacity-test/).

### How much does Freedom smog charge for a Clean Truck Check?

Freedom smog has not published prices with us; call (209) 622-9156 for a quote. Published California prices are usually $50–$135 per vehicle for an OBD test and $190–$200 for a smoke opacity test, plus CARB's annual fee ($32.13 in 2026). See the [cost guide](https://ctcfinder.com/guide/cost/).

### Is Freedom smog a CARB-credentialed tester?

Freedom smog appears on CARB's public Clean Truck Check tester list, last checked November 1, 2026. Only credentialed testers can submit results to CARB; after the test, confirm the passing result shows for your vehicle in CTC-VIS.

## Other testers nearby

- **[A&B Truck repair, Inc.](https://ctcfinder.com/tester/a-and-b-truck-repair-inc-modesto/)** — 959 S 9th St, Modesto, CA 95355 — (209) 527-6971 — 4 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[CleanTruck209](https://ctcfinder.com/tester/cleantruck209-modesto/)** — 2708 Deerfield Pl, Modesto, CA 95355 — (209) 556-2254 — 4 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[JM Transportation LLC](https://ctcfinder.com/tester/jm-transportation-llc-modesto/)** — 3305 Copeland Ct, Modesto, CA 95355 — (408) 512-7925 — 4 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Smog & DMV](https://ctcfinder.com/tester/smog-and-dmv-modesto/)** — 1616 Oakdale Rd Suite 1, Modesto, CA 95355 — (209) 735-1241 — 4 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Amanpreet Singh](https://ctcfinder.com/tester/amanpreet-singh-modesto/)** — Modesto, CA 95356 — (231) 286-0800 — 5 mi. Services: not listed.
- **[Jacob Palleschi](https://ctcfinder.com/tester/jacob-palleschi-modesto/)** — Modesto, CA 95356 — (209) 596-6496 — 5 mi. Services: mobile testing, OBD testing.