---
title: "Piston Dorado — Clean Truck Check, San Jose, CA | CTC Finder"
description: "Piston Dorado in San Jose, 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/piston-dorado-san-jose/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Piston Dorado

Clean Truck Check tester in San Jose, CA (Santa Clara 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 | San Jose, CA 95112 |
| County | Santa Clara County |
| Phone | (650) 457-4699 |
| Mobile testing | Yes |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | Yes |
| Motorhomes | Yes |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks Piston Dorado 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 Santa Clara County

Piston Dorado is one of 79 testing businesses in Santa Clara County on CARB's public tester list. 67 of them offer mobile testing and 27 do smoke opacity tests. In San Jose itself there are 41 listed businesses, 36 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 Piston Dorado offer mobile Clean Truck Check testing?

Yes. Piston Dorado 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 Piston Dorado test a 2012 or older diesel truck?

Yes. Piston Dorado 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 Piston Dorado charge for a Clean Truck Check?

Piston Dorado has not published prices with us; call (650) 457-4699 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 Piston Dorado a CARB-credentialed tester?

Piston Dorado 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

- **[FJM Truck and Trailer Center](https://ctcfinder.com/tester/fjm-truck-and-trailer-center-san-jose/)** — 1540 Industrial Ave, San Jose, CA 95112 — (408) 417-2520 — 1 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Keyes ST Smog Check](https://ctcfinder.com/tester/keyes-st-smog-check-san-jose/)** — 331 Keyes St, San Jose, CA 95112 — (408) 831-8947 — 1 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[San Jose Conservation Corps - San Jose, CA](https://ctcfinder.com/tester/san-jose-conservation-corps-san-jose-ca-san-jose/)** — 1560 Berger Dr, San Jose, CA 95112 — (408) 472-7093 — 1 mi. Services: mobile testing, OBD testing.
- **[CS Autoworks](https://ctcfinder.com/tester/cs-autoworks-san-jose/)** — San Jose, CA 95110 — (408) 636-6210 — 1 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Eco Box Recycling Inc](https://ctcfinder.com/tester/eco-box-recycling-inc-san-jose/)** — 385 Willow St, San Jose, CA 95110 — (408) 639-1373 — 1 mi. Services: OBD testing.
- **[Mike's Technical](https://ctcfinder.com/tester/mikes-technical-san-jose/)** — San Jose, CA 95116 — (949) 817-9249 — 2 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.