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CDL Test: Inspection questions and answers

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Inspection

44 questions

  1. #1

    Front (steering) tires must have tread depth of at least:

    1. 2/32 inch
    2. 4/32 inch
    3. 1/32 inch
    4. 8/32 inch

    Answer: B. Front tires: at least 4/32 inch in every major groove; other tires: 2/32 inch.

    Source: North Dakota CDL Manual (2025-2027), 2.1.3You need at least 4/32-inch tread depth in every major groove on front tires.

  2. #2

    Steering wheel play of more than how much can make it hard to steer?

    1. 2 degrees
    2. 5 degrees
    3. 45 degrees
    4. 10 degrees (about 2 inches at the rim of a 20-inch wheel)

    Answer: D. More than 10 degrees of free play makes steering difficult.

    Source: North Dakota CDL Manual (2025-2027), 2.1.3

  3. #3

    Cargo and its securing devices must be checked within the first how many miles of a trip?

    1. 50
    2. 5
    3. 150
    4. 500

    Answer: A. Check within the first 50 miles, then every 3 hours or 150 miles and after every break.

    Source: Michigan CDL Manual (2022), 3.1

  4. #4

    After the first check, cargo securement should be rechecked:

    1. Only at the end of the day
    2. Every 500 miles
    3. Every 3 hours or 150 miles, whichever comes first
    4. Never if the load is sealed

    Answer: C. Recheck every 3 hours or 150 miles and after every break.

    Source: Michigan CDL Manual (2022), 3.1After you have driven for 3 hours or 150 miles.

  5. #5

    How many steps are in the standard pre-trip inspection method in the CDL manual?

    1. Three
    2. Seven
    3. Ten
    4. Twelve

    Answer: B. The seven-step method: overview, engine compartment, cab, lights, walkaround, signal lights, brake checks.

    Source: North Dakota CDL Manual (2025-2027), 2.1.5

  6. #6

    To test hydraulic brakes for leaks, pump the pedal three times, then hold firm pressure for five seconds. The pedal should:

    1. Slowly sink to the floor
    2. Bounce back and forth
    3. Go down about one inch
    4. Not move

    Answer: D. If the pedal moves, there may be a leak — get it fixed before driving.

    Source: North Dakota CDL Manual (2025-2027), 2.1.5The pedal should not move.

  7. #7

    To test the service brake during the pre-trip inspection, you should:

    1. Go about 5 mph and push the brake pedal firmly
    2. Brake hard at highway speed
    3. Set the parking brake and accelerate
    4. Pump the brake at 30 mph

    Answer: A. At about 5 mph, a firm stop should not pull to one side or be delayed.

    Source: North Dakota CDL Manual (2025-2027), 2.1.5

  8. #8

    Which warning devices must you carry for a stopped vehicle?

    1. Two flags
    2. One flare
    3. Three reflective warning triangles
    4. Six cones

    Answer: C. Emergency equipment includes three reflective warning triangles, a fire extinguisher and spare fuses (if needed).

    Source: North Dakota CDL Manual (2025-2027), 2.1.3

  9. #9

    What happens if a federal or state inspector judges your vehicle to be unsafe?

    1. It is put “out of service” until it is fixed
    2. It may continue the trip at a lower speed
    3. It may finish the trip but must be repaired within a week
    4. It is fined and released once the driver signs a report

    Answer: A. The inspector may declare it out of service, and it stays out until it is fixed.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 29If they judge the vehicle to be unsafe, they will put it “out of service” until it is fixed.

  10. #10

    Rust around the wheel nuts may mean that:

    1. the wheel bearings need grease
    2. the nuts are loose
    3. the tire pressure is too high
    4. the rim has been welded

    Answer: B. Rust around wheel nuts can show looseness, so check their tightness.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 30Rust around wheel nuts may mean the nuts are loose—check tightness.

  11. #11

    If what portion of the leaves in a leaf spring are missing, the vehicle is put “out of service”?

    1. One-tenth or more
    2. One-half or more
    3. One-fourth or more
    4. Three-fourths or more

    Answer: C. Missing leaves are a serious defect; one-fourth or more makes the vehicle out of service.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 30If onefourth or more are missing, it will put the vehicle “out of service,” but any defect could be dangerous.

  12. #12

    What is the minimum tread depth required on tires other than the front tires?

    1. 2/32 inch
    2. 1/32 inch
    3. 3/32 inch
    4. 4/32 inch

    Answer: A. Front tires need 4/32 inch in every major groove; other tires need 2/32 inch.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 29You need 2/32 inch on other tires.

  13. #13

    Why is a broken exhaust system dangerous?

    1. It can cause the brakes to fade and the engine to stall
    2. It can let poison fumes into the cab or sleeper berth
    3. It can make the steering wheel loose and hard to turn
    4. It can overcharge the battery and damage the alternator

    Answer: B. A leaking or broken exhaust can send poison fumes into the cab or sleeper berth.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 31A broken exhaust system can let poison fumes into the cab or sleeper berth.

  14. #14

    Which of these tire problems should you look for during an inspection?

    1. Tires of the same size on the same axle
    2. Valve stems with caps
    3. Radial and bias-ply tires used together
    4. Tires inflated to the correct pressure

    Answer: C. Using radial and bias-ply tires together is listed as a tire problem.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 29Radial and bias-ply tires used together.

  15. #15

    After starting the engine, air pressure should build from 50 to 90 psi within:

    1. one minute
    2. five minutes
    3. ten minutes
    4. three minutes

    Answer: D. Normal air pressure build-up from 50 to 90 psi should take no more than three minutes.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 32Pressure should build from 50 to 90 psi within three minutes.

  16. #16

    During the pre-trip, the ABS light on the dash stays on after the engine starts. What does this mean?

    1. The ABS is not working properly
    2. The ABS is working normally
    3. The brake fluid is low
    4. The parking brake is still set

    Answer: A. The ABS light should come on and then turn off; if it stays on, the ABS is not working properly.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 32Light on dash should come on and then turn off. If it stays on, the ABS is not working properly.

  17. #17

    On a trailer, where is the ABS warning light that indicates a malfunction if it stays on?

    1. Red light on the right front of the trailer
    2. Yellow light on the left rear of the trailer
    3. Amber light on the roof of the trailer
    4. Green light on the trailer's landing gear

    Answer: B. A yellow light on the left rear of the trailer that stays on means the ABS is not working properly.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 32For trailers only, if the yellow light on the left rear of the trailer stays on, the ABS is not working properly.

  18. #18

    Air pressure should be built up to the governor cut-out, which is usually around:

    1. 60 to 80 psi
    2. 90 to 100 psi
    3. 120 to 140 psi
    4. 150 to 180 psi

    Answer: C. The governor usually cuts out at around 120 to 140 psi, but know your vehicle's requirements.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 32Build air pressure to governor cut-out (usually around 120 - 140 psi.

  19. #19

    Before getting out to check the lights during the pre-trip, you should set the parking brake, turn off the engine and:

    1. leave the key in the ignition
    2. hang the key on the mirror
    3. give the key to a helper
    4. take the key with you

    Answer: D. Set the parking brake, turn off the engine and take the key with you.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 33Make sure the parking brake is set, turn off the engine, and take the key with you.

  20. #20

    How do you test the parking brake during the pre-trip inspection?

    1. Put the vehicle in a low gear and gently pull forward against the set brake
    2. Drive at 20 mph and apply the parking brake
    3. Release the brake and check that the vehicle rolls freely
    4. Set the brake and shake the vehicle by hand

    Answer: A. Set the brake, select a low gear and gently pull forward; it must hold the vehicle.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 35Gently pull forward against parking brake to make sure the parking brake holds.

  21. #21

    How long should you keep a copy of your vehicle inspection report in the vehicle?

    1. One hour
    2. One day
    3. One week
    4. One month

    Answer: B. The next driver can learn about any problems you found from the copy kept for one day.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 35Keep a copy of your report in the vehicle for one day.

  22. #22

    When should you sign the last vehicle inspection report?

    1. Always, before you start the engine, whether or not defects were found
    2. Only if you found no defects at all during your own inspection
    3. Only if defects were noted and certified as repaired or not needing repair
    4. Only after you have driven the first 50 miles without a problem

    Answer: C. Sign only when any noted defects were certified as repaired or unnecessary to repair.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 31You must sign the report only if defects were noted and certified to be repaired or not needed to be repaired.

  23. #23

    On a cab-over-engine vehicle, what should you check during the walkaround inspection?

    1. That the cab is tilted forward
    2. That the cab doors are locked from the inside only
    3. That the hood latch is open
    4. That the primary and secondary safety cab locks are engaged

    Answer: D. Cab-over-engine vehicles need both primary and secondary safety cab locks engaged.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 33Primary and secondary safety cab locks engaged (if cab-over-engine design).

  24. #24

    Why should you do a pre-trip inspection the same way each time?

    1. You learn all the steps and are less likely to forget something
    2. The examiner always requires the same order on the skills test
    3. Federal law fixes the order of each step of the inspection
    4. It lowers fuel use because the engine idles for less time

    Answer: A. Doing it the same way each time helps you learn the steps and avoid forgetting something.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 31You should do a pre-trip inspection the same way each time so you will learn all the steps and be less likely to forget something.

  25. #25

    Before each trip, a truck driver must make sure that the truck is not overloaded and that the cargo is:

    1. sealed and photographed
    2. balanced and secured
    3. weighed on a public scale
    4. loaded toward the rear

    Answer: B. The truck must not be overloaded, and the cargo must be balanced and secured before every trip.

    Source: North Dakota CDL Manual (AAMVA model), Section 2, p. 31You must make sure the truck is not overloaded and the cargo is balanced and secured before each trip.

  26. #26

    During the CDL vehicle inspection test, you will NOT have to:

    1. name or point to the items you inspect
    2. crawl under the vehicle
    3. explain to the examiner what you are inspecting
    4. use the checklist provided in the manual

    Answer: B. The manual says you must name, point to and explain each item, but you will not have to crawl under the vehicle.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 139You will NOT have to crawl under the vehicle.

  27. #27

    During the air brake check, the air governor cuts out at approximately:

    1. 60 to 80 psi
    2. 90 to 110 psi
    3. 150 to 170 psi
    4. 120 to 140 psi

    Answer: D. Build air pressure to governor cutout, which occurs at approximately 120-140 psi or the level specified by the manufacturer.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 141Build the air pressure to governor cutout and identify the range of activation. This will occur at approximately 120 – 140 psi OR level specified by the manufacturer.

  28. #28

    In the air leakage rate test, the air pressure may drop no more than how many pounds in one minute for a combination vehicle?

    1. 4 pounds
    2. 2 pounds
    3. 3 pounds
    4. 6 pounds

    Answer: A. For a combination vehicle the pressure may drop no more than four pounds in one minute; for a single vehicle, three pounds.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 141Inspect the air gauge to see if the air pressure drops no more than three (3) pounds in one (1) minute (single vehicle or trailer without airbrakes) or four (4) pounds in one (1) minute (combination vehicle) after initial stabilization.

  29. #29

    In the emergency brake test, the parking brake valve should close (pop out) between:

    1. 5 psi and 15 psi
    2. 50 psi and 70 psi
    3. 20 psi and 45 psi
    4. 80 psi and 100 psi

    Answer: C. The parking (emergency) brake valve should pop out between 20 psi and 45 psi, or at the level specified by the manufacturer.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 141The parking brake (or emergency brake) valve should close (pop out) between 20 psi and 45 psi (no less than 20 psi and no more than 45 psi) OR level specified by the manufacturer.

  30. #30

    Failure to explain and demonstrate all four parts of the air brake check correctly will result in:

    1. an automatic failure of the CDL Vehicle Inspection test
    2. a warning from the examiner
    3. loss of points only on the air brake portion
    4. a second attempt at the air brake check

    Answer: A. Not performing all four parts of the air brake check correctly is an automatic failure of the vehicle inspection test.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 141Failure to explain and demonstrate (perform) all four (4) parts of the air brake check correctly will result in an automatic failure of the CDL Vehicle Inspection test.

  31. #31

    When checking engine belts for snugness, how much play is allowed at the center of the belt?

    1. Up to 1/4 inch
    2. Up to 2 inches
    3. Up to 3 inches
    4. Up to 3/4 inch

    Answer: D. Belts should be snug, with up to 3/4 inch play at the center, and without cracks or frays.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 131Check the following belts for snugness (up to 3/4 inch play at center of belt), cracks, or frays:

  32. #32

    For manual slack adjustors, the brake pushrod should not move more than how far when pulled by hand with the brakes released?

    1. Half an inch
    2. One inch
    3. Two inches
    4. Three inches

    Answer: B. With the brakes released, the pushrod of a manual slack adjustor should not move more than one inch when pulled by hand.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 133For manual slack adjustors, the brake pushrod should not move more than one inch (with the brakes released) when pulled by hand.

  33. #33

    When checking the engine oil level with the dipstick, the level must be:

    1. exactly at the full mark
    2. below the refill mark
    3. at the bottom of the dipstick
    4. above the refill mark

    Answer: D. The oil level must be within the safe operating range, above the refill mark.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 131See that oil level is within safe operating range. Level must be above refill mark.

  34. #34

    When checking coolant level during the pre-trip inspection, if the engine is hot you should:

    1. remove the cap slowly to release pressure
    2. not remove the radiator cap
    3. remove the cap only with the engine running
    4. add water through the cap

    Answer: B. If the engine is hot, do not remove the radiator cap.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 144Caution: If the engine is hot, do not remove the radiator cap.

  35. #35

    During the pre-trip inspection test, what will NOT earn you credit for checking tire inflation?

    1. Simply kicking the tires
    2. Using a tire gauge
    3. Mentioning the use of a tire gauge
    4. Checking that valve stems are accessible

    Answer: A. You will not get credit if you simply kick the tires; you must check inflation with a tire gauge.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 134You will not get credit if you simply kick the tires to check for proper inflation.

  36. #36

    On a vehicle with emissions after-treatment equipment, the diesel exhaust fluid (DEF) tank level is adequate when it is:

    1. more than 1/2 tank
    2. more than 3/4 tank
    3. more than 1/8 tank
    4. completely full

    Answer: C. The DEF level is adequate if there is more than 1/8 of a tank.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 134Checks DEF tank to ensure the level of diesel exhaust fluid in the tank is adequate (more than 1/8th tank)

  37. #37

    When inspecting wheel rims, which condition is not allowed?

    1. Clean surface
    2. Welding repairs on the rim
    3. Straight rims
    4. Rim bolt holes that are round

    Answer: B. Rims cannot have welding repairs.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 134Rims cannot have welding repairs.

  38. #38

    When inspecting the fifth wheel, you look into the gap to check that the locking jaws are:

    1. open around the kingpin
    2. resting on the apron
    3. lubricated with grease
    4. fully closed around the kingpin

    Answer: D. Look into the fifth wheel gap and check that the locking jaws are fully closed around the kingpin.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 135Look into fifth wheel gap and check that locking jaws are fully closed around the kingpin.

  39. #39

    When checking the coupling, the trailer should be:

    1. laying flat on the fifth wheel skid plate with no gap
    2. raised about an inch above the skid plate, with a small gap
    3. tilted slightly forward, with a gap at the rear of the skid plate
    4. resting on its landing gear instead of on the skid plate

    Answer: A. Check that the trailer is laying flat on the fifth wheel skid plate (no gap).

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 135Check that the trailer is laying flat on the fifth wheel skid plate (no gap).

  40. #40

    If you apply for a Class A CDL, you will perform one of how many versions of the pre-trip inspection?

    1. Two
    2. Three
    3. Four
    4. Five

    Answer: C. Class A applicants perform one of four equivalent versions; Class B or C applicants perform one of three.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 137If you are applying for a Class A CDL, you will be required to perform one of the four versions of a pre-trip inspection in the vehicle you have brought with you for testing.

  41. #41

    Committing an "unsafe act" during the vehicle inspection test, such as forgetting to set the parking brake, may result in:

    1. a small point deduction only, and the test continues as normal
    2. a second chance to repeat the step before the examiner scores it
    3. an automatic failure, and the examiner may terminate the test
    4. a verbal warning that is not recorded on your test score sheet

    Answer: C. An unsafe act may result in an automatic failure, and the examiner may terminate the test.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 139Committing an "unsafe act" (e.g., forgetting to set the parking brake) may result in an automatic failure and the test may be terminated by the examiner.

  42. #42

    During the vehicle inspection test, when exiting the vehicle you must:

    1. set the parking brake(s) and place the vehicle in neutral
    2. leave the engine in gear and the parking brake released
    3. release the parking brake and leave the vehicle in low gear
    4. turn the key to the accessory position and leave the brakes released

    Answer: A. When exiting the vehicle, you must set the parking brake(s) and place the vehicle in neutral.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 139When exiting the vehicle, you must set the parking brake(s) and place the vehicle in neutral.

  43. #43

    For combination vehicles, in addition to the dashboard ABS indicator, which light should turn on and then off during the check?

    1. The passenger side trailer clearance light
    2. The front marker light on the tractor
    3. The trailer brake light
    4. The rear driver's side trailer ABS light

    Answer: D. For combination vehicles only, the rear driver's side trailer ABS light should turn on then off, if equipped.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 139ABS indicator on dashboard; (and for combination vehicles only, the rear driver's side trailer ABS light should turn on then off), if equipped.

  44. #44

    Which signs may indicate that lug nuts are loose?

    1. A clean, dry hub
    2. Rust trails or shiny threads
    3. Fresh paint on the wheel
    4. Evenly worn tread

    Answer: B. There should be no signs of rust trails or shiny threads, which may show looseness.

    Source: North Dakota CDL Manual (AAMVA model), Section 11, p. 145Inspect that lug nuts are not loose and there are no signs of rust trails or shiny threads that may show looseness.
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