---
title: "Credentialed Tstr. — Clean Truck Check, Rocklin, CA"
description: "Credentialed Tstr. in Rocklin, 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/credentialed-tstr-rocklin/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Credentialed Tstr.

Clean Truck Check tester in Rocklin, CA (Placer 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 | Rocklin, CA 95765 |
| County | Placer County |
| Phone | (916) 538-7777 |
| Website | carbdieseltest.com |
| Mobile testing | Yes |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | Yes |
| Motorhomes | Yes |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks Credentialed Tstr. 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 Placer County

Credentialed Tstr. is one of 39 testing businesses in Placer County on CARB's public tester list. 36 of them offer mobile testing and 22 do smoke opacity tests. In Rocklin itself there are 6 listed businesses, 6 of them mobile.

## 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 Credentialed Tstr. offer mobile Clean Truck Check testing?

Yes. Credentialed Tstr. 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 Credentialed Tstr. test a 2012 or older diesel truck?

Yes. Credentialed Tstr. 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 Credentialed Tstr. charge for a Clean Truck Check?

Credentialed Tstr. has not published prices with us; call (916) 538-7777 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 Credentialed Tstr. a CARB-credentialed tester?

Credentialed Tstr. 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

- **[CARByourRide](https://ctcfinder.com/tester/carbyourride-rocklin/)** — 6248 Arctic Loon Way, Rocklin, CA 95765 — (209) 598-8650 — 1 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Credentialed tester in Rocklin](https://ctcfinder.com/tester/credentialed-tester-in-rocklin-rocklin/)** — 6518 Lonetree Blvd 2043, Rocklin, CA — (916) 243-5089 — 2 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[CARB Compliance Testing](https://ctcfinder.com/tester/carb-compliance-testing-rocklin/)** — Rocklin, CA 95677 — (916) 538-7777 — 3 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Dave's Clean Truck](https://ctcfinder.com/tester/daves-clean-truck-rocklin/)** — 4188 Lakeside Dr, Rocklin, CA 95677 — (279) 782-1851 — 3 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[J4 Clean Truck Testing](https://ctcfinder.com/tester/j4-clean-truck-testing-rocklin/)** — 5155 5th St, Rocklin, CA 95677 — (916) 365-1066 — 3 mi. Services: mobile testing, OBD testing.
- **[CA Emissions Group](https://ctcfinder.com/tester/ca-emissions-group-roseville/)** — 1100 Melody Ln Ste, Roseville, CA 95678 — (916) 266-2026 — 4 mi. Services: mobile testing, OBD testing, motorhome testing.