Commercial Truck Smog + Emissions California
Commercial trucks with GVWR over 14,000 lbs follow the Periodic Smoke Inspection Program (PSIP) instead of biennial smog. PSIP requires an annual smoke opacity test for diesel trucks 1991+. Gasoline commercial trucks under 14k lbs follow standard biennial smog. We handle both at our test+repair locations.
Overview
California has TWO emissions programs: (1) Standard Smog Check Program for cars/trucks/SUVs ≤14,000 lbs GVWR. (2) Periodic Smoke Inspection Program (PSIP) for diesel commercial vehicles >14,000 lbs GVWR. PSIP is annual; smog is biennial.
Key facts
- ✓ Diesel commercial >14k lbs GVWR (Class 4-8 trucks): PSIP annual smoke test
- ✓ Gasoline commercial ≤14k lbs GVWR: Standard biennial smog
- ✓ Diesel commercial ≤14k lbs (lighter work trucks): Standard biennial smog
- ✓ Buses, semis, dump trucks, refuse trucks: PSIP program
- ⚠ Commercial fleet operators: CARB also requires DECAL stickers for vehicles operating in CA
Common questions
What's the difference between Smog Check and PSIP?
Smog Check is biennial (every 2 years) for personal + light commercial vehicles ≤14k lbs GVWR. PSIP is annual smoke-opacity testing for heavy commercial diesels >14k lbs GVWR. Different equipment, different procedures.
Do you handle Class 4-8 commercial trucks?
For PSIP smoke tests, contact us — we coordinate with PSIP-certified facilities. For biennial smog on lighter commercial trucks (≤14k lbs), we test in-house at our test+repair locations.
Commercial smog services at our network
Closest locations equipped to handle commercial vehicles: