K1 Smog

Clean Truck Check tester in Hayward, CA (Alameda County).

K1 Smog appears on CARB's public list of credentialed Clean Truck Check testers. It lists OBD testing, motorhome testing.

Location
24087 Mission Blvd, Hayward, CA 94544
County
Alameda County
Phone
(510) 582-2500
Mobile testing
No (test at the shop)
OBD testing
Yes
Smoke opacity (non-OBD)
No
Motorhomes
Yes
Credentialed testers
1
Last verified

Call (510) 582-2500 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. Typical published prices for an OBD test are $50–$135 per vehicle (see cost guide).

Which trucks K1 Smog can test

The test CARB requires depends on the engine's fuel and model year. Based on the services K1 Smog lists on CARB's tester list:

Your vehicleTest requiredThis tester
Diesel, model year 2013 or newerOBD scanYes
Alternative fuel (natural gas, propane), 2018 or newerOBD scanYes
Diesel, model year 2012 or older (no OBD)Smoke opacity test (SAE J1667) plus visual inspectionNot listed
California-registered motorhomeSame test as above by engine year, once a yearYes

For a 2012 or older diesel, the nearest listed tester with smoke opacity testing is JR Trucking Services in Hayward, about 1 mile away. See listing.

If you need a tester at your yard, the nearest listed tester that offers mobile testing is Jaswinder Singh in Hayward, about 1 mile away. See listing.

Clean Truck Check testers in Alameda County

K1 Smog 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 Hayward itself there are 18 listed businesses, 17 of them mobile. All testers in Alameda 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 K1 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 K1 Smog offer mobile Clean Truck Check testing?

Not according to CARB's tester list; plan to bring the truck to the tester. The nearest listed mobile tester is Jaswinder Singh (about 1 mile).

Can K1 Smog test a 2012 or older diesel truck?

K1 Smog does not list smoke opacity testing, which older non-OBD diesel trucks need. The nearest listed tester that does is JR Trucking Services (about 1 mile). Trucks from 2013 on get an OBD scan instead.

How much does K1 Smog charge for a Clean Truck Check?

K1 Smog has not published prices with us; call (510) 582-2500 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 K1 Smog a CARB-credentialed tester?

K1 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 Hayward

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.

Call (510) 582-2500