---
title: "Rayo’s Heavy Duty Testing — Clean Truck Check, Duarte, CA"
description: "Rayo’s Heavy Duty Testing in Duarte, CA is on CARB's Clean Truck Check tester list. Offers mobile testing, OBD testing, motorhome testing. Phone, address and…"
url: "https://ctcfinder.com/tester/rayos-heavy-duty-testing-duarte/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# Rayo’s Heavy Duty Testing

Clean Truck Check tester in Duarte, CA (Los Angeles 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 | 2191 Flagstone Ave, Duarte, CA 91010 |
| County | Los Angeles County |
| Phone | (626) 341-4482 |
| Mobile testing | Yes |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | No |
| Motorhomes | Yes |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks Rayo’s Heavy Duty Testing 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 | Not listed |
| California-registered motorhome | Same test as above by engine year, once a year | Yes |

For a 2012 or older diesel, the nearest listed tester with smoke opacity testing is Clear View Opacity testing in Duarte, about 1 mile away. [See listing](https://ctcfinder.com/tester/clear-view-opacity-testing-duarte/).

## Clean Truck Check testers in Los Angeles County

Rayo’s Heavy Duty Testing is one of 516 testing businesses in Los Angeles County on CARB's public tester list. 465 of them offer mobile testing and 190 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 Rayo’s Heavy Duty Testing offer mobile Clean Truck Check testing?

Yes. Rayo’s Heavy Duty Testing 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 Rayo’s Heavy Duty Testing test a 2012 or older diesel truck?

Rayo’s Heavy Duty Testing does not list smoke opacity testing, which older non-OBD diesel trucks need. The nearest listed tester that does is [Clear View Opacity testing](https://ctcfinder.com/tester/clear-view-opacity-testing-duarte/) (about 1 mile). Trucks from 2013 on get an OBD scan instead.

### How much does Rayo’s Heavy Duty Testing charge for a Clean Truck Check?

Rayo’s Heavy Duty Testing has not published prices with us; call (626) 341-4482 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 Rayo’s Heavy Duty Testing a CARB-credentialed tester?

Rayo’s Heavy Duty Testing 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

- **[Clear View Opacity testing](https://ctcfinder.com/tester/clear-view-opacity-testing-duarte/)** — 2620 Broderick Ave, Duarte, CA 91010 — (909) 906-8241 — 1 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Foothill Automotive Services](https://ctcfinder.com/tester/foothill-automotive-services-monrovia/)** — 150 East Pomona Avenue, Monrovia, CA 91016 — (626) 357-5015 — 3 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Jarhead Fleet](https://ctcfinder.com/tester/jarhead-fleet-monrovia/)** — 252 North Canyon Boulevard, Monrovia, CA 91016 — (626) 944-0618 — 3 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Brothers Truck N Trailer Repair Inc](https://ctcfinder.com/tester/brothers-truck-n-trailer-repair-inc-baldwin-park/)** — 14846 Arrow Hwy, Baldwin Park, CA 91706 — (626) 560-0890 — 3 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Fernando Mendez](https://ctcfinder.com/tester/fernando-mendez-baldwin-park/)** — Baldwin Park, CA 91706 — (626) 421-2929 — 3 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.
- **[Jesus Estrada](https://ctcfinder.com/tester/jesus-estrada-baldwin-park/)** — Baldwin Park, CA 91706 — (562) 239-5409 — 3 mi. Services: not listed.