49 CFR 396: DOT Vehicle Inspection and Maintenance

Regulatory citation: 49 CFR Part 396, Inspection, Repair, and Maintenance (Federal Motor Carrier Safety Administration), with Appendix G, Minimum Periodic Inspection Standards

What Are the FMCSA Inspection, Repair and Maintenance Rules?

Part 396 requires motor carriers and intermodal equipment providers to keep commercial motor vehicles (CMVs) in safe operating condition. It covers systematic maintenance programs, driver inspections before and after each trip, annual inspections, roadside inspection follow-up, inspector qualifications and recordkeeping. It applies to every carrier operating CMVs in interstate commerce, including trucks, tractors, trailers, buses and the chassis used to move intermodal containers.

The rule works alongside Part 393, which sets the parts and accessories every vehicle must have, such as brakes, lights, tires and coupling devices. Part 393 says what equipment is required. Part 396 says how the carrier makes sure that equipment stays in working order.

Why Vehicle Maintenance Matters

Brake defects, worn tires, and lighting and coupling failures are long-standing causes of truck crashes and among the most common out-of-service violations found at roadside. The Vehicle Maintenance category of FMCSA's Safety Measurement System draws largely on these inspection results, and poor scores raise the chance of an investigation. A documented maintenance program is also the main defense when a crash investigation examines whether a defect was known and ignored.

Core Obligations

1. Run a Systematic Maintenance Program (396.3(a))

Every carrier and intermodal equipment provider must systematically inspect, repair and maintain, or cause to be systematically inspected, repaired and maintained, all motor vehicles and intermodal equipment under its control. Parts and accessories must be in safe and proper operating condition at all times. Pushout windows, emergency doors and emergency door marking lights in buses must be inspected at least every 90 days.

2. Keep Maintenance Records for Each Vehicle (396.3(b) and (c))

For each vehicle controlled for 30 consecutive days or more, the carrier must keep identification details, including company number, make, serial number, year and tire size, and the owner's name if the carrier does not own it. It must also keep a schedule showing the nature and due dates of inspections and maintenance, and a record of inspection, repairs and maintenance showing the date and type. Push-out window and emergency door inspections on buses must also be recorded. Records must be kept where the vehicle is housed or maintained for 1 year and for 6 months after the vehicle leaves the carrier's control.

3. Never Operate an Unsafe Vehicle (396.7)

A motor vehicle may not be operated in a condition likely to cause an accident or a breakdown. If a vehicle becomes unsafe during operation, it may only continue to the nearest place where repairs can safely be made, and only if that is less hazardous than remaining on the highway.

4. Respond to Roadside Inspections (396.9)

Vehicles declared out of service at roadside may not be operated until the out-of-service defects are repaired. The driver must give the inspection report to the carrier when they arrive at the next terminal or facility, or mail it if they will not get there within 24 hours. Within 15 days of the inspection, the carrier must certify that all violations noted have been corrected by completing the certification on the report. Since July 22, 2026, the carrier only has to return the signed report to the issuing state agency if that agency asks for it. The carrier must keep a copy for 12 months.

5. Complete Post-Trip Inspection Reports (396.11)

At the end of each day's work, the driver must prepare a driver vehicle inspection report (DVIR) for each vehicle driven, covering at least service brakes including trailer brake connections, parking brake, steering mechanism, lighting devices and reflectors, tires, horn, windshield wipers, rear vision mirrors, coupling devices, wheels and rims, and emergency equipment. Since 2014 for property carriers and 2020 for passenger carriers, a DVIR is only required when the driver finds or is told of a defect or deficiency. A final rule effective March 23, 2026 confirmed in the regulation text that DVIRs may be completed and signed electronically.

6. Repair and Certify Before the Next Trip (396.11(a)(3))

Before a vehicle with a reported defect is driven again, the carrier must repair any defect that would affect safe operation and certify on the DVIR that the defect has been repaired or that repair is unnecessary. The carrier must keep the original DVIR, the certification of repairs and the next driver's certification of review for 3 months from the date the report was prepared.

7. Require Pre-Trip Checks by Drivers (396.13)

Before driving, a driver must be satisfied that the vehicle is in safe operating condition. If the last DVIR noted defects, the driver must review it and sign it to acknowledge the review, but only if the defects were certified as repaired or not needing repair. Many carriers add a full pre-trip walkaround to meet this duty and to catch problems early.

8. Pass an Annual Inspection (396.17 and Appendix G)

Every CMV, including each trailer and intermodal chassis, must be inspected at least once every 12 months against the minimum standards in Appendix G. The inspection covers brake systems, coupling devices, exhaust, fuel, lighting, safe loading, steering, suspension, frame, tires, wheels and rims, windshield glazing and wipers, among other items. A carrier may accept a state periodic inspection program that FMCSA has found comparable, or an inspection done by another qualified party, as long as it meets the standard.

9. Use Qualified Inspectors and Keep Annual Records (396.19, 396.21 and 396.25)

Annual inspections must be done by an inspector who understands the standards and can identify defective components, through training, experience or a combination of both. The carrier must keep evidence of each inspector's qualifications. Anyone who inspects, maintains, services or repairs brakes, including brake adjustment, must meet the brake inspector qualifications in 396.25. The annual inspection report must identify the inspector, the carrier, the date, the vehicle and the components inspected, and must certify that the vehicle passed. The original or a copy must be kept for 14 months, and a copy of the report, or a decal or other documentation, must be carried on the vehicle.

Common Compliance Approaches

Schedule Preventive Maintenance by Mileage and Time

Set service intervals using the manufacturer's recommendations and adjust them for duty cycle. Track each unit's next service in a fleet maintenance system rather than on paper.

Close the DVIR Loop

Use an electronic DVIR system that routes defects straight to the shop and blocks dispatch until the repair is certified. Most audit findings come from defects that were reported but never signed off.

Inspect Trailers and Rental Units Too

Carriers often maintain tractors well but lose track of trailers, interchanged equipment and short-term rentals. Keep the annual inspection and maintenance records for every unit under your control for 30 days or more.

Learn From Roadside Inspections

Review every inspection report, not just those with violations, to find patterns such as lights, tires or brake adjustment by terminal, vehicle type or shop.

Example: Vehicle Maintenance in Practice

A regional less-than-truckload carrier receives a roadside inspection in which one tractor is placed out of service for two brakes out of adjustment. The driver calls the shop, and a mobile technician qualified under 396.25 adjusts the brakes on site. The terminal manager certifies the repair on the inspection report within 3 days. Because the state's instructions say it does not need the report back, the carrier files a copy for 12 months. The maintenance manager then pulls six months of DVIRs and roadside reports and finds that brake adjustment problems cluster on one tractor model whose automatic slack adjusters were installed wrong. The shop corrects the installation across that model, adds a brake stroke check to every preventive maintenance service, and retrains drivers on the pre-trip brake check.

Related regulations: DOT hours of service, DOT driver qualification files, OSHA lockout/tagout.

Note: This summary covers federal FMCSA requirements for vehicles in interstate commerce. Many states apply similar rules to intrastate carriers and run their own periodic inspection programs. Hazardous materials cargo tanks also need the periodic tests and inspections in 49 CFR Part 180. Always check the current regulation text and FMCSA guidance.

Frequently Asked Questions

Do drivers have to complete a DVIR if there are no defects?

No. Since 2014 for property carriers and 2020 for passenger carriers, drivers only need to prepare a DVIR when they find or are told of a defect or deficiency. Drivers must still inspect the vehicle before driving.

How long must DVIRs be kept?

The carrier must keep the original DVIR, the certification of repairs and the driver's review certification for 3 months from the date the report was prepared.

Can a state inspection count as the annual inspection?

Yes, if FMCSA has determined the state's periodic inspection program is comparable to or more stringent than the federal standard. Otherwise, the carrier must arrange an inspection that meets Appendix G.

Do I still have to mail roadside inspection reports back to the state?

Only if the issuing state agency requests it. Since July 22, 2026, carriers must still certify corrections within 15 days and keep a copy for 12 months, but return the report only when asked.