CDL Practice Test

CDL Vehicle Inspection Practice Questions

Vehicle Inspection makes up 7 of every 50 questions on a Tigertest CDL practice test. Here are 10 of the 60 questions on it, each with the answer and the reason.

Updated 2026-11-10 by the Tigertest team. Covers the CDL general knowledge exam. 80% to pass on the real test.

1. 1. What is the first step in conducting a proper pre-trip inspection?

   • A.Test the horn and lights
   • B.Review the last post-trip report
   • C.Check the engine oil level
   • D.Inspect the tires for damage

   Answer: B. You should always start by reviewing the previous driver's post-trip inspection report to identify any known issues before beginning your own inspection.

2. 2. When checking engine oil during pre-trip inspection, what indicates the oil level is acceptable?

   • A.Oil level at or just below the minimum mark
   • B.Oil level slightly above the maximum mark
   • C.Oil level exactly at the maximum mark
   • D.Oil level between minimum and maximum marks

   Answer: D. The oil level should be between the minimum and maximum marks on the dipstick to ensure adequate lubrication without overfilling.

3. 3. What is the minimum legal tread depth for front tires on a commercial vehicle?

   • A.4/32 of an inch
   • B.2/32 of an inch
   • C.3/32 of an inch
   • D.1/16 of an inch

   Answer: A. Front tires must have at least 4/32 inch of tread depth, while all other tires need at least 2/32 inch for safe operation.

4. 4. What should you do if you find a brake adjustment that exceeds the adjustment limit during inspection?

   • A.Adjust the brake yourself if possible
   • B.Note it for the next scheduled maintenance
   • C.Put the vehicle out of service immediately
   • D.Continue driving but check again later

   Answer: C. Any brake that exceeds the adjustment limit is a critical safety defect that requires the vehicle to be put out of service until repaired.

5. 5. When inspecting the steering system, what indicates a problem that requires immediate attention?

   • A.Steering wheel is not perfectly centered
   • B.Steering wheel cover is worn
   • C.More than 10 degrees of free play
   • D.Power steering fluid is slightly low

   Answer: C. Excessive steering wheel free play (more than 10 degrees) indicates worn components that could cause loss of control and must be repaired immediately.

6. 6. When inspecting leaf springs during pre-trip inspection, what should you look for?

   • A.Cracked, broken, or missing leaves
   • B.Springs should be perfectly straight
   • C.Springs should be completely rigid
   • D.Springs should have some flexibility

   Answer: A. Inspect leaf springs for cracked, broken, or missing leaves, as these defects can lead to suspension failure and loss of vehicle control.

7. 7. What indicates a problem with the exhaust system during inspection?

   • A.Warm temperature of exhaust components
   • B.Normal exhaust pipe vibration
   • C.Slight discoloration of exhaust pipes
   • D.Loose, damaged, or missing parts

   Answer: D. Loose, damaged, or missing exhaust system parts can cause dangerous fume leaks into the cab and must be repaired before driving.

8. 8. When checking the fifth wheel during pre-trip inspection, what should you verify about the locking mechanism?

   • A.It should be partially open for easy coupling
   • B.It should be fully closed and locked
   • C.It should have visible grease buildup
   • D.It should move freely in all directions

   Answer: B. The fifth wheel locking mechanism must be fully closed and locked to ensure the trailer remains securely attached during transport.

9. 9. How should you test that all required lights are working properly during pre-trip inspection?

   • A.Have someone else operate the switches
   • B.Turn on each light and walk around to verify
   • C.Check electrical connections without testing
   • D.Visual inspection from the driver's seat only

   Answer: B. You must physically turn on each light system and walk around the vehicle to visually confirm all required lights are functioning properly.

10. 10. During a trip, what should prompt you to pull over and inspect your vehicle?

    • A.Every two hours of driving time
    • B.When fuel level reaches half full
    • C.Only when warning lights appear
    • D.Any unusual noise, vibration, or smell

    Answer: D. Any unusual noise, vibration, or smell during driving may indicate a developing problem that requires immediate inspection to prevent breakdowns or accidents.