Warner Mountain Smog
Clean Truck Check tester in Alturas, CA (Modoc County).
- Mobile testing
- OBD test
- Smoke opacity
- Motorhomes
Warner Mountain Smog appears on CARB's public list of credentialed Clean Truck Check testers. It lists mobile testing, OBD testing, smoke opacity (non-OBD) testing, motorhome testing. Mobile testing means the tester can come to your yard or job site.
- Location
- 599 Cougar Dr, Alturas, CA 96101
- County
- Modoc County
- Phone
- (530) 640-3424
- Mobile testing
- Yes — comes to your yard
- OBD testing
- Yes
- Smoke opacity (non-OBD)
- Yes
- Motorhomes
- Yes
- Credentialed testers
- 1
- Last verified
Call (530) 640-3424 Open in Google Maps
Before you call
- Have your VIN, odometer reading and plate number ready.
- Your vehicle must be registered in CTC-VIS and the annual compliance fee paid; the tester submits the result to CARB.
- Ask for the price per vehicle and any mobile trip fee. Typical published prices for an OBD test are $50–$135 per vehicle (see cost guide).
Which trucks Warner Mountain Smog can test
The test CARB requires depends on the engine's fuel and model year. Based on the services Warner Mountain Smog lists on CARB's tester list:
| 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 Modoc County
Warner Mountain Smog is one of 2 testing businesses in Modoc County on CARB's public tester list. 2 of them offer mobile testing and 1 do smoke opacity tests. All testers in Modoc County.
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. You can test up to 90 days before a deadline. Get a free email reminder before each one.
How to check a tester's credential
CARB publishes its Clean Truck Check tester list, where Warner Mountain Smog appears as of November 1, 2026. Listing there is optional, so a missing name does not always mean a tester is not credentialed. After the test, check that the passing result shows for your vehicle in CTC-VIS; that is what counts for compliance.
Frequently asked questions
Does Warner Mountain Smog offer mobile Clean Truck Check testing?
Yes. Warner Mountain Smog 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 Warner Mountain Smog test a 2012 or older diesel truck?
Yes. Warner Mountain Smog lists smoke opacity testing, the test CARB requires for diesel trucks of model year 2012 and older (no OBD). See OBD vs smoke opacity.
How much does Warner Mountain Smog charge for a Clean Truck Check?
Warner Mountain Smog has not published prices with us; call (530) 640-3424 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.
Is Warner Mountain Smog a CARB-credentialed tester?
Warner Mountain Smog 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 near Alturas
-
Daniel Straub
- Mobile testing
- OBD test
- Motorhomes
Source: CARB's public Clean Truck Check tester list, last checked . Listing on CARB's list is optional for testers, so some credentialed testers are not shown. Services, hours and prices change; please confirm with the tester before you go. Something wrong? Send a correction.