Monkey's Smog Center
Clean Truck Check tester in Oakdale, CA (Stanislaus County).
- Mobile testing
- OBD test
Monkey's Smog Center appears on CARB's public list of credentialed Clean Truck Check testers. It lists mobile testing, OBD testing. Mobile testing means the tester can come to your yard or job site.
- Location
- 217 W F St, Oakdale, CA 95361
- County
- Stanislaus County
- Phone
- (209) 595-6293
- Mobile testing
- Yes — comes to your yard
- OBD testing
- Yes
- Smoke opacity (non-OBD)
- No
- Motorhomes
- No
- Credentialed testers
- 1
- Last verified
Call (209) 595-6293 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 Monkey's Smog Center can test
The test CARB requires depends on the engine's fuel and model year. Based on the services Monkey's Smog Center 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 | Not listed |
| California-registered motorhome | Same test as above by engine year, once a year | Not listed |
For a 2012 or older diesel, the nearest listed tester with smoke opacity testing is John Pascale in Oakdale, about 1 mile away. See listing.
Clean Truck Check testers in Stanislaus County
Monkey's Smog Center is one of 53 testing businesses in Stanislaus County on CARB's public tester list. 47 of them offer mobile testing and 22 do smoke opacity tests. In Oakdale itself there are 5 listed businesses, 5 of them mobile. All testers in Stanislaus 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 Monkey's Smog Center 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 Monkey's Smog Center offer mobile Clean Truck Check testing?
Yes. Monkey's Smog Center 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 Monkey's Smog Center test a 2012 or older diesel truck?
Monkey's Smog Center does not list smoke opacity testing, which older non-OBD diesel trucks need. The nearest listed tester that does is John Pascale (about 1 mile). Trucks from 2013 on get an OBD scan instead.
How much does Monkey's Smog Center charge for a Clean Truck Check?
Monkey's Smog Center has not published prices with us; call (209) 595-6293 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 Monkey's Smog Center a CARB-credentialed tester?
Monkey's Smog Center 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 Oakdale
-
Chris Horton
- Mobile testing
- OBD test
- Motorhomes
-
John Pascale
- Mobile testing
- OBD test
- Smoke opacity
- Motorhomes
-
K7 Group LLC
- Mobile testing
- OBD test
-
Steven Ingram
- Mobile testing
- OBD test
- Smoke opacity
- Motorhomes
-
Coast Machine Inc
- Mobile testing
- OBD test
- Smoke opacity
- Motorhomes
-
Freedom smog
- Mobile testing
- OBD test
- Smoke opacity
- 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.