Department of Transportation Truck Inspections

What to Expect When a DOT Inspector Examines Your CMV

All commercial motor vehicles (CMV) that weigh more than 10,000 pounds must undergo annual DOT inspections. A DOT inspection is an inspection conducted by the Department of Transportation to ensure that all the CMV parts and accessories are safe to use, in good condition, and working properly.

There are six primary levels of DOT inspections. These may be conducted anywhere by a qualified DOT inspector or state police officer. The following list of the different levels includes an explanation of the methods used in assessing the vehicle and its drive.

Level I: North American Standard Inspection

Department of Transportation worker holding clipboard conducting inspections on commercial vehicles

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At this level of inspection, the inspector will be meticulous in checking the driver's documents, in addition to looking for drugs, alcohol or hazardous materials that the driver may be transporting. This list includes:

In checking the vehicle, the evaluation will look at the following parts and accessories:

  • Seatbelt
  • Brakes
  • Brake lamps
  • Coupling devices
  • Exhaust system
  • Emergency exits and/or electrical cables and systems in the engine and battery compartments (buses)
  • Frame
  • Fuel system
  • Headlamps
  • Lamps on projecting loads
  • Safe loading
  • Securement of cargo
  • Steering mechanism
  • Stop lamps
  • Suspension
  • Tail lamps
  • Tires
  • Trailer bodies
  • Turn signals
  • Wheels, rims, and hubcaps
  • Windshield wipers

Level II: Walk-Around Driver/Vehicle Inspection

Inspector looking at tires on commercial vehicle

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This inspection is almost identical to the level I evaluation, except that the inspector will not check any of the parts that require physically getting under the CMV. You may want to consider using a DOT driver vehicle checklist or mobile app to learn what goes into conducting a vehicle safety inspection.

Level III: Driver-Only Inspection

Female truck driver through the windshield

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At a level III inspection, you can expect an in-depth examination of the following list:

  • Driver’s license
  • Medical card
  • Driver’s daily log
  • Seatbelt​
  • Driver and Vehicle Inspection Report
  • Driver incident history
  • Hazmat requirements

Level IV: Special Inspection

close-up of tires on commercial vehicle being inspected

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The level IV special inspection refers to a one-time examination conducted to take a closer look at a particular feature of the vehicle. This is usually done to invalidate a previous claim about the vehicle — in order to support or refute a study or suspected trend.

Level V: Vehicle-Only Inspection

woman inspecting a commercial vehicle without the driver present

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A level V inspection can be conducted at any location and includes everything in level I regarding the vehicle — but without a driver present.

Level VI: Enhanced NAS Inspection for Radioactive Shipments

Department of transportation employee holding a clipboard with checklist on it

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Since DOT regulations came into effect as of January 1, 2005, all CMVs transporting highway route controlled quantities (HRCQ) of radioactive material are required to pass the North American Standard Level VI Inspection. This inspection includes:

  • Inspecting for radiological shipments
  • Inspection procedures
  • Enhancements to level I
  • Radiological requirements
  • Enhanced out of service criteria

How You Can Best Prepare for an Inspection

Commercial vehicle with working headlights driving along empty road

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Drivers can learn the dangers of driving defective vehicles and how to detect and report problems for repairs well before a bigger issue arises. One of the best ways to do this is to perform a simple walk-around inspection before and after every trip the vehicle makes, including:

Checking the Tires

Even though tires rarely blow out, they do tend to deflate slowly until the vehicle can no longer be driven. Check each tire for air and use a digital tire pressure gauge to check out tires that seem deflated. Also, be sure to know the rules and regulations in your state about mudflaps. Some states provide specific requirements for mudflaps/splash guards on the rear of the vehicle (to keep spray and debris tossed up by the tires from hitting the windshields of the following traffic).

Testing the Lights

Malfunctioning lights, bulbs, and electric signals can be a safety hazard. Be sure to check not only the brake lights but also the headlights, high beams, and low beams by turning on the engine and switching each one on systematically.

Looking for Cracks

Any cracks in the windows (even small, tiny chips) can quickly become much worse if they aren't addressed right away. Be sure to regularly check for hairline cracks and "stars" caused by flying gravel.

To ensure that drivers are passing inspections with flying colors, it's important to know what the inspection criteria includes and how to be proactive about maintaining a safe CMV.