---
title: "Dora Lopez — Clean Truck Check, Fremont, CA | CTC Finder"
description: "Dora Lopez in Fremont, CA is on CARB's Clean Truck Check tester list. Offers mobile testing, OBD testing, smoke opacity (non-OBD) testing. Phone, address and…"
url: "https://ctcfinder.com/tester/dora-lopez-fremont/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Dora Lopez

Clean Truck Check tester in Fremont, CA (Alameda 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 | Fremont, CA 94536 |
| County | Alameda County |
| Phone | (650) 208-9960 |
| Mobile testing | Yes |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | Yes |
| Motorhomes | No |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks Dora Lopez 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 | Not listed |

## Clean Truck Check testers in Alameda County

Dora Lopez is one of 85 testing businesses in Alameda County on CARB's public tester list. 79 of them offer mobile testing and 37 do smoke opacity tests. In Fremont itself there are 12 listed businesses, 12 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 Dora Lopez offer mobile Clean Truck Check testing?

Yes. Dora Lopez 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 Dora Lopez test a 2012 or older diesel truck?

Yes. Dora Lopez 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 Dora Lopez charge for a Clean Truck Check?

Dora Lopez has not published prices with us; call (650) 208-9960 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 Dora Lopez a CARB-credentialed tester?

Dora Lopez 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

- **[Autotek CNG Services](https://ctcfinder.com/tester/autotek-cng-services-fremont/)** — 4299 Peralta Blvd Suite A, Fremont, CA 94536 — (510) 445-3055 — 1 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Kevin J Hutchins](https://ctcfinder.com/tester/kevin-j-hutchins-fremont/)** — Fremont, CA 94536 — (510) 449-7888 — 1 mi. Services: mobile testing, OBD testing.
- **[Longoria Bros Clean Truck Check](https://ctcfinder.com/tester/longoria-bros-clean-truck-check-fremont/)** — 37810 Von Euw Cmn, Fremont, CA 94536 — (510) 712-0483 — 1 mi. Services: mobile testing, OBD testing.
- **[MingxuanHu](https://ctcfinder.com/tester/mingxuanhu-fremont/)** — 4837 El Poco Cmn, Fremont, CA 94536 — (909) 569-3922 — 1 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Sumanjit Punia](https://ctcfinder.com/tester/sumanjit-punia-fremont/)** — Fremont, CA 94536 — (510) 402-3858 — 1 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Yong Hu](https://ctcfinder.com/tester/yong-hu-fremont/)** — Fremont, CA 94536 — (626) 955-9566 — 1 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.