---
title: "John Daugherty — Clean Truck Check, Los Angeles, CA"
description: "John Daugherty in Los Angeles, 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/john-daugherty-los-angeles/"
updated: "2026-11-01"
publisher: "CTC Finder (independent directory, not affiliated with CARB)"
---

# John Daugherty

Clean Truck Check tester in Los Angeles, 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 | Los Angeles, CA 90032 |
| County | Los Angeles County |
| Phone | (626) 756-0196 |
| Mobile testing | Yes |
| OBD testing | Yes |
| Smoke opacity (non-OBD) | Yes |
| Motorhomes | Yes |
| Credentialed testers | 1 |
| Last verified | 2026-11-01 |

## Which trucks John Daugherty 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 Los Angeles County

John Daugherty 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. In Los Angeles itself there are 69 listed businesses, 60 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 John Daugherty offer mobile Clean Truck Check testing?

Yes. John Daugherty 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 John Daugherty test a 2012 or older diesel truck?

Yes. John Daugherty 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 John Daugherty charge for a Clean Truck Check?

John Daugherty has not published prices with us; call (626) 756-0196 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 John Daugherty a CARB-credentialed tester?

John Daugherty 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

- **[Chris Chappel](https://ctcfinder.com/tester/chris-chappel-los-angeles/)** — Los Angeles, CA 90032 — (619) 405-9758 — 1 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[Jeff's Automobile Repair Service](https://ctcfinder.com/tester/jeffs-automobile-repair-service-los-angeles/)** — 5196 Alhambra Ave, Los Angeles, CA 90032 — (626) 278-0787 — 1 mi. Services: OBD testing, motorhome testing.
- **[Arceo Transport LLC](https://ctcfinder.com/tester/arceo-transport-llc-los-angeles/)** — 303 North Marianna Avenue, Los Angeles, CA 90063 — (213) 453-4932 — 2 mi. Services: smoke opacity (non-OBD) testing.
- **[Jose Cervantes](https://ctcfinder.com/tester/jose-cervantes-los-angeles/)** — Los Angeles, CA 90063 — (323) 307-1231 — 2 mi. Services: mobile testing.
- **[Sergio Melendez](https://ctcfinder.com/tester/sergio-melendez-los-angeles/)** — Los Angeles, CA 90063 — (323) 394-4145 — 2 mi. Services: mobile testing, OBD testing, motorhome testing.
- **[CTC Mobile Tester](https://ctcfinder.com/tester/ctc-mobile-tester-alhambra/)** — 1325 Elm St, Alhambra, CA 91803 — (626) 313-6409 — 2 mi. Services: mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing.