https://www.truckinsure.com/90-day-tr...

Here's a look at the requirements for 90-day inspections, as required by the state of California.

If your truck has a GVW (gross vehicle weight) rating of 10,000 lbs. or more in California, it must be inspected every 90 days.
BIT inspections ensure the safe operation of regulated vehicles by motor carriers.

Each 90-day inspection report at minimum must include:

Identification of the vehicle
Date and nature of each inspection and any repair performed.
Signature of the motor carrier’s authorized representative attesting to the inspection and to the completion of all required repairs.