Most non-gasoline vehicles over 14,000 lb GVWR that operate in California.
| Vehicle | Typical schedule | Test |
|---|---|---|
| Diesel engine 2013 or newer | Twice a year | OBD scan |
| Diesel engine 2012 or older | Twice a year | Smoke opacity and visual inspection |
| Alternative fuel, engine 2018 or newer | Twice a year | OBD scan |
| Alternative fuel, engine 2017 or older | Twice a year | Visual inspection only |
| California motorhome, recreation or emergency only | Once a year | Depends on engine |
| Agricultural vehicle meeting CARB’s definition | Once a year | Depends on engine |
Out-of-state trucks that operate in California are included. Their deadline follows the last digit of the VIN. Starting October 2027, OBD-equipped vehicles move to four tests a year. Motorhomes and agricultural vehicles stay annual. Confirm the date in CTC-VIS. Program page: CARB Clean Truck Check.
