Official CDL Test

🛑 Official CDL Knowledge Test

This is the real deal — the official CDL test section designed to help you prepare, prove your knowledge, and move forward with confidence. Whether you’re starting fresh or rebuilding your career, this test is your gateway to better opportunities.

📘 Covers core CDL topics with real-world relevance
📊 Your score helps match you with jobs and schools
🏆 Compete on the leaderboard and track your progress
🚀 Completing this test unlocks more personalized matches

Online CDL Test

This test evaluates your readiness to pass the official Commercial Driver’s License (CDL) exam, ensuring you have the knowledge needed to operate safely and legally as a professional truck driver. A solid understanding of CDL requirements helps drivers avoid violations, improve safety, and enhance career opportunities.

Topics Covered:

General knowledge, air brakes, and combination vehicle rules
Pre-trip inspection procedures and vehicle control fundamentals
Hazardous materials regulations and endorsements
Hours of Service (HOS) compliance and logbook requirements
Traffic laws, road safety, and defensive driving techniques

Passing this test demonstrates your ability to meet CDL standards and operate with professionalism and skill.

1 / 32

1. How can you determine if your vehicle is equipped with an anti-lock braking system (ABS)?

Check for a yellow ABS malfunction lamp on the instrument panel.

Look for wheel speed sensor wires that are coming from the rear of your brakes.

Check if your vehicle was manufactured after March 1, 1998. (Such vehicles are required to have the panel light.)

All of the above can work.

2 / 32

2. If you're driving a vehicle with an automatic transmission, when should you downshift?

If you feel you're driving too fast

If you're going down a steep downgrade

When your engine speed increases

If you start to get drowsy

3 / 32

What is the penalty for driving a commercial motor vehicle (CMV) without a CDL?

A fine of up to $2,000 and mandatory jail time

A fine of up to $1,000 and possible jail time

A fine of up to $5,000 or possible jail time

A fine of at least $5,000 and possible jail time

4 / 32

4. It has just reached freezing. Which of the following areas may be slippery?

A wet-looking road

A shaded area

A bridge

All of the above

5 / 32

5. An anti-lock braking system (ABS) will

increase your stopping distance.

let you drive faster.

keep your wheels from locking when you brake hard.

increase your vehicle's stopping power.

6 / 32

6. What is a common cause of tire fires?

Underinflated tires

All of the above

Overinflated tires

Cold tires

7 / 32

Which of the following are safe ways to communicate with others?

Tapping your horn when it's legal and you're about to pass

Flashing your brake lights when you're about to slow down

All of the above

Flashing your headlights at night when you're about to pass

8 / 32

Letting the air out of hot tires

will cool them down. You will be able to continue your trip sooner.

will have no effect at all.

is a good idea because the extra pressure will be relieved.

is a bad idea because when the tires cool off, the pressure will be too low.

9 / 32

9. In which of the following two situations should you downshift?

Starting down a hill and entering a curve

Starting down a hill and finishing a curve

Starting up a hill and entering a curve

Starting up a hill and finishing a curve

10 / 32

10. The most important hand signal you should agree on with a helper is

“Go.”

“Stop.”

“Faster.”

“Turn up the music.”

11 / 32

11. What is the best way to figure out how many seconds of following distance you have?

Use the stopwatch on your cell phone to determine how long it takes you to reach a mile marker after the vehicle in front of you has passed it.

Get 1/4 closer to the car in front of you, then back off again. Multiply how long this took you by four to give the following distance.

Wait until the vehicle ahead of you passes a shadow or landmark. Then count the seconds until you reach it.

Send a text message to a friend to text you back in ten seconds. See how far you have traveled in that time.

12 / 32

12. The minimum tread depth for tires other than the front tires is

2/32 inch.

4/32 inch.

8/32 inch.

1 inch.

13 / 32

13.

What will help a drunk sober up?

A glass of water

Fresh air

Coffee

Time

14 / 32

14. How many tie-downs are required for a 20-foot load?

15 / 32

15. How many reflective warning triangles must you carry with you for emergencies?

16 / 32

16. What are the main differences between aggressive driving and road rage?

The level of anger

All of the above

Whether it's intentional

The outcome of the situation

17 / 32

17. To maintain alertness during your trip, you should

schedule your trip for the daytime hours.

do all of the above.

get 8–9 hours of sleep beforehand.

avoid medications that cause drowsiness.

18 / 32

18. You don't want to be a distracted driver, so you

avoid using your cell phone until you reach your destination.

read maps or use your phone only when there are no other vehicles around you.

have all your emotionally difficult conversations in the first hour of driving.

smoke, eat, and drink only on straight portions of the road.

19 / 32

19. Which of the following are serious traffic violations that may cause you to lose your CDL privileges?

Traveling at 15 mph or more above the posted speed limit

All of the above

Playing music too loudly

Talking on a cell phone

20 / 32

20. For how long will you lose your CDL privileges if you are convicted of a second DUI offense?

Ten years minimum

Life

Five years minimum

Three years minimum

21 / 32

21. Total stopping distance equals

Perception distance + reaction distance.

Perception distance + reaction distance + braking distance.

Reaction distance + braking distance.

Reaction distance + braking distance + signal distance.

22 / 32

22. If you are confronted by an aggressive driver, you should

ignore rude gestures and refuse to react negatively.

call the police from your cell phone if you can do it safely.

avoid eye contact.

do all of the above.

23 / 32

23. If the engine is not overheated, is it completely safe to remove the radiator cap?

Yes.

Yes, as long as there is no overflow.

Yes, as long as the radiator isn't damaged.

24 / 32

24. Which of the following should you check during your trip?

Pressure gauges

Cargo covers

All of the above

Mirrors

25 / 32

25. What is the main reason to perform a vehicle inspection?

To check the cleanliness of your vehicle

To make sure your paint is not chipped

Employer liability

Safety

26 / 32

26. How do you test a vehicle's hydraulic brakes for leaks?

Apply firm pressure for 5 seconds. Then pump the brakes 3 times.

Pump the brakes 3 times. Then apply firm pressure for 10 seconds.

Pump the brakes 5 times. Then apply firm pressure for 3 seconds.

Pump the brakes 3 times. Then apply firm pressure for 5 seconds.

27 / 32

27. On which of the following types of fires should you NOT use a B:C fire extinguisher?

Gasoline

Grease

Electrical

Wood

28 / 32

28. Which of the following are parts of the suspension system?

Pitman arm

Lock ring

Bearing plate

All of the above

29 / 32

29. How long does it take a typical tractor-trailer to clear a double railroad track?

14 seconds

More than 30 seconds

10 seconds

More than 15 seconds

30 / 32

30. What is the best way to check what is happening behind and to the sides of your vehicle?

Adjust your mirrors before you start your trip and check them regularly.

Just turn your head and look at your blind spots.

Check your reflection in other vehicles.

Stop every 50 miles and look around.

31 / 32

31. Which of these is NOT part of the basic method for shifting up?

Releasing the clutch and pressing the accelerator at the same time

Pushing in the clutch and shifting into a higher gear at the same time

Releasing the clutch

Accelerating while pressing the clutch and turning toward the driver's side

32 / 32

32. You should put the starter switch key into your pocket while you perform the pre-trip inspection because

someone could steal the truck.

it could damage the starting mechanism.

any of the above could occur.

someone could start and move the truck.

Your score is

The average score is 28%

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