A 90-day BIT inspection is a carrier-performed safety inspection required for specific regulated vehicles under California Vehicle Code Section 34505.5. Each covered vehicle must be inspected at least every 90 days, with shorter intervals when needed for safe operation. The carrier must keep a record that identifies the vehicle, documents the inspection and repairs, and shows the required attestation.
This periodic vehicle inspection is different from the CHP terminal inspection. CHP Motor Carrier Specialists review a sample of vehicles, maintenance records, driver records, and hazardous materials practices when applicable during the terminal visit. Our California BIT inspections and audits service covers what is required and how we help you prepare.
How California’s 90-Day Inspection Cycle Works
California’s 90-day inspection rule applies through the carrier’s systematic inspection, maintenance, and lubrication program. The deadline runs by vehicle, so one current unit does not cure another unit that passed its due date.
Here’s an example. If Unit 214 was inspected 72 days ago and Unit 305 was inspected 96 days ago, Unit 305 is overdue even when both vehicles share the same terminal and maintenance shop.
A vehicle kept out of service for longer than 90 calendar days does not need another inspection while it remains out of service. It must be inspected before it returns to highway operation.
Which Vehicles Need a 90-Day BIT Inspection?
The rule applies to specific commercial vehicles based on factors such as vehicle type, weight, and use. Some vehicles are exempt under California law.
Covered categories include:
- Motortrucks with three or more axles and a gross vehicle weight rating above 10,000 pounds.
- Truck tractors.
- Trailers, semitrailers, pole or pipe dollies, auxiliary dollies, and logging dollies used in covered combinations, excluding the trailer types named in the statute.
- A motor truck above 10,000 pounds GVWR towing a covered trailer when the coupled combination exceeds 40 feet, subject to the statutory exclusions.
- Vehicles or combinations transporting hazardous materials covered by the law.
- Commercial motor vehicles rated at 26,001 pounds or higher, plus covered towing combinations described in Section 34500(k).
Vehicle weight is only part of the answer. The rule can also depend on the number of axles, whether the vehicle tows a trailer, the type of trailer involved, and whether the vehicle is based outside California.
Interstate vehicles that are not physically based in California do not have to keep their 90-day reports in California. They remain subject to CHP inspection while present in the state. If CHP finds maintenance program deficiencies, the carrier may be required to produce the records within 10 working days.
What Does the Inspection Have to Cover?
California law has five minimum inspection areas. The carrier may inspect additional systems based on the vehicle, its use, the maintenance schedule, or a condition reported by the driver.
- Brake adjustment
- Brake system components and leaks
- Steering and suspension systems
- Tires and wheels
- Vehicle connecting devices
The CHP 108 Truck and/or Tractor Maintenance & Safety Inspection form provides a practical format for trucks, tractors, and trailers. Its starred items identify the minimum Section 34505.5 requirements, while the full form also covers lights, warning devices, air systems, frames, wheel seals, electrical wiring, fuel systems, exhaust components, and other safety items.
CHP 108 is available from CHP and may be reproduced privately. A carrier may use another paper or electronic form when the record captures the information required by law.
The carrier also needs to keep documentation showing that the person performing the inspection meets the qualifications that apply to the work being performed. If your inspectors need documented training, our California BIT Inspector Certification Training can help you establish those qualifications and keep the right records on file.
What Your 90-Day Inspection Record Must Include
The 90-day inspection record is part of the compliance requirement. A completed inspection with a missing or untraceable report creates a recordkeeping failure during a CHP review.
Each report must include:
- Positive identification of the vehicle, such as make, model, license number, or company unit number.
- The date and nature of the inspection.
- Any repair performed in response to the inspection.
- The motor carrier’s authorized representative’s signature attesting to the inspection and completion of required repairs.
The carrier must retain the reports for two years at its designated terminals and make them available to authorized CHP personnel upon request. Also, electronic inspection and maintenance records are accepted. The printout must include the vehicle identification plus the inspection and repair information required by Section 34505.5.
Use a Fleet Calendar That Tracks Every Unit
The safest tracking system starts with one current vehicle roster and one accountable owner. A calendar can be a fleet maintenance platform, a shared spreadsheet, or another system your staff will actually keep current.
Build these controls into the process:
- Record the last inspection date and next due date for every covered unit.
- Set an internal reminder before day 90 so the shop has time to schedule the vehicle.
- Add newly acquired, leased, or transferred vehicles before dispatch.
- Place a return-to-service inspection hold on units parked for longer than 90 days.
- Link each inspection report to repair orders and final repair closeout.
- Review the roster after sales, transfers, and unit-number changes.
Inspection due dates should be tracked in a shared system, not by one employee. Anyone responsible for maintenance records should be able to see which vehicle is due next and find its most recent inspection report.
What Happens When a Vehicle Is Overdue
An overdue covered vehicle puts the carrier outside the required inspection cycle. Remove the unit from normal dispatch, arrange the inspection, and document any required repair before it resumes service.
During a CHP terminal inspection, Motor Carrier Specialists compare the vehicle sample with the maintenance records. A single late report is a deficiency. A pattern of overdue units, incomplete repairs, or missing records can show that the maintenance program is not functioning as required. That’s why you need to make sure every vehicle has the necessary reports.
CHP does not issue citations for violations discovered during the terminal inspection itself. It assigns a safety compliance rating. An unsatisfactory category leads to correction direction and a reinspection within 120 days.
Review Your 90-Day Records Before CHP Arrives
Choose a few vehicles from your active fleet and follow the paperwork from start to finish. Confirm that each unit has a current inspection report, that any repairs are documented, and that the next due date is easy to find. Then compare the report with the vehicle itself.
Our principals served as CHP Motor Carrier Specialists, and our senior partner managed the Northern Division Motor Carrier Safety Unit for 36 years. That experience helps us spot missed inspections, incomplete repair records, and filing problems before CHP reviews them.
For help with the full terminal review, see our California BIT inspection checklist and BIT inspections and audits service page.
Get Help With 90-Day Inspection Compliance
How We Support 90-Day Inspection Compliance
We help carriers organize their inspection records before CHP asks for them. Our team previously worked in CHP motor carrier enforcement, so we understand which records inspectors request and where problems usually appear. Learn more about our BIT inspection support services.
We can review your current files, flag vehicles nearing the 90-day deadline, and set up a tracking process your maintenance team can use. If a CHP review is already scheduled, we can also help your staff gather the records and correct missing or incomplete documentation.
Our training and seminars help fleet staff understand BIT requirements and keep inspection records current throughout the year.
Need help getting your inspection records in order?
Call us at (541) 761-8619 or visit our BIT Inspections & Audits page to learn how we can help your operation stay compliant year-round.
Updated: September 25, 2026