CDL Permit Practice Test (50 Questions Answers)

CDL Permit Practice Test (50 Questions Answers): In order to get this special license, you must first take and pass the required CDL knowledge test and skills tests. Using this free sample test correctly will prepare you to take and pass these tests. This practice test is consist of 50 questions and is followed by an answer key.

Taking our free CDL Permit Practice Test and any other practice Endorsement Tests that apply to your vehicle type, and studying the explanations of the correct answers for the practice tests, you can find out how well you are prepared for the actual Commercial Driver’s License Exam and what material you need to review again.

CDL Permit Practice Test (50 Questions Answers)

Test Name	CDL Practice Test 2025
Language	English
License	CDL (Class A, B, or C),
Total Questions	50 Knowledge Practice Test
Test For	Commercial Driver License
Test Preparation	Driving Knowledge
Country	USA
Explanation	No

0 votes, 0 avg

CDL General Knowledge Test 6

1 / 50

Which of the following is a sign of a tire failure?

A) A loud “bang”

B) Vibration

C) All of the above

D) The steering wheel pulls to one side

2 / 50

f one-fourth of a multileaf spring is missing, which of the following is most likely to happen?

A) It will have no effect.

B) It will make it hard to steer.

C) It will put the vehicle out of service.

D) It will cause a pop-pop-pop sound.

3 / 50

Which of the following should you examine when inspecting the front of your vehicle?

A) Condition of brakes

B) Condition of steering system

C) Condition of shock absorbers

D) All of the above

4 / 50

What causes brakes to fade?

A) Frozen brake pads

B) Slowing down from high speeds too quickly

C) Using the brakes too lightly when going downhill

D) Coasting

5 / 50

If the steering feels heavy or hard, it is probably a sign of

A) worn brakes.

B) battery failure.

C) engine problems.

D) tire problems.

6 / 50

Which of the following is true about overhead clearance?

A) Repaving or packed snow increases the clearance height.

B) A loaded truck is higher than an empty one.

C) An empty van is higher than a loaded van.

D) Posted heights are always correct.

7 / 50

You are stopped on the shoulder of a curve that prevents approaching traffic from seeing your vehicle. How far back should you place your last warning device?

A) 200 feet

B) 100 feet

C) 10 feet

D) 500 feet

8 / 50

Why must you tab or keep shipping papers related to hazardous materials in special places?

A) f the driver is in an accident and cannot speak, people must know the hazards involved.

B) Because they must be delivered first

C) Because you must know what products you can load together, and which you cannot

D) In case there are no placards

9 / 50

Which of the following is true about empty trucks?

A) They have better traction.

B) They are easier to steer.

C) They require less braking power.

D) They require greater stopping distance.

10 / 50

Which of the following emergency equipment should be carried in the truck at all times?

A) spare electrical fuses (if the truck has fuses)

B) a fully charged 5 B:C fire extinguisher

C) All of the above

D) reflective warning triangles or flares

11 / 50

How often must drivers of trucks and truck tractors conduct a safety inspection?

A) Before driving, every 3 hours during driving, and after driving

B) Every 5 hours and after driving

C) Before driving

D) After driving

12 / 50

You are driving a 60-foot rig at 55 mph. How many seconds of space should you have between you and the vehicle ahead?

A) 6 seconds

B) 8 seconds

C) 7 seconds

D) 5 seconds

13 / 50

The controlled braking method is used

A) by applying the brakes as hard as you can without locking the wheels.

B) when making large steering wheel movements

C) by applying the brakes slowly.

D) to make the wheels lock.

14 / 50

he proper distance to use high beams is at least _______________ away from an approaching vehicle.

A) 50 feet

B) 25 feet

C) 500 feet

D) 1,000 feet

15 / 50

If you have to steer away from what’s ahead in order to avoid a crash, which of the following is the best action to take?

A) Turn, then countersteer once you have cleared the obstacle

B) Hit the brakes.

C) Turn very sharply to clear whatever is in your way

D) Apply the brakes while turning.

16 / 50

When driving down a steep curve in the snow, you should

A) brake hard.

B) use the speed retarder.

C) turn as gently as possible.

D) use the engine brake.

17 / 50

Which of the following is one of the potential causes of fire in the electrical system?

A) Poor ventilation

B) Duals that touch

C) Flammable cargo

D) Short circuits due to damaged insulation

18 / 50

A broken coolant hose while driving

A) can cause a fire

B) increases the chances of tire failure.

C) causes the heater to fail.

D) causes the air-conditioner to fail.

19 / 50

Where and when is it best to downshift?

A) After starting up a hill

B) After starting down a hill

C) Before speeding up

D) Before entering a curve

20 / 50

Why don’t new trucks use the same gear for going down a hill as they would for going up a hill?

A) They have low friction parts.

B) They take up more fuel.

C) They have weaker engines.

D) They have more air drag.

21 / 50

You should inspect the tires every _________ when driving in very hot weather.

A) one hour or every 50 miles

B) two hours or every 100 miles

C) four hours or every 400 miles

D) three hours or every 150 miles

22 / 50

What is the proper way to make a right turn when you are driving a long vehicle?

A) Keep the rear of the vehicle far away from the curb

B) Turn wide to the left as you start the turn.

C) Turn quickly to stop other drivers from hitting you.

D) Turn wide as you complete the turn.

23 / 50

What is the total stopping distance when driving a heavy vehicle on dry pavement at 55 mph?

A) 4 1/2 seconds

B) 5 seconds

C) 6 seconds

D) 7 1/2seconds

24 / 50

Some vehicles have automatic transmissions. Why is it important to select a low range when going down grades?

A) To allow the transmission to shift up

B) To get greater engine braking

C) To prevent a hydraulic brake failure

D) To prevent hydroplaning

25 / 50

You are stopped on an incline. How do you keep from rolling back?

A) Pump the accelerator hard

B) Put on the parking brake

C) Engage the clutch

D) Shift to neutral

26 / 50

Which of the following statements is true about alcohol?

A) A few beers are the same as a few shots of whiskey.

B) Alcohol increases your ability to drive.

C) Some people are not affected by alcohol

D) If you eat a lot first, you will not get drunk

27 / 50

At speeds below 40 mph, you need at—————for each————of vehicle length.

A) two seconds; 30 feet

B) one second; 10 feet

C) one second; 20 feet

D) two seconds; 10 feet

28 / 50

Which of the following is one of the best ways to deal with tailgaters in heavy traffic?

A) Speed up to increase the distance between you and the tailgater.

B) Increase your following distance.

C) Turn on your tail lights.

D) Brake quickly several times to flash your brake lights.

29 / 50

To extinguish an electrical fire,

A) use the A:B:C extinguisher on the flames of the fire.

B) use the B:C extinguisher on the base of the fire.

C) use a lot of water.

D) pull into a service station and wait for qualified firefighters.

30 / 50

You are approaching a vehicle for a pre-trip inspection. What should be the first step?

A) Fastening your seatbelt

B) Putting the vehicle key in your pocket

C) Starting the engine

D) Writing a written report on the condition of the vehicle

31 / 50

What is black ice?

A) Oil

B) Freshly paved tar

C) Fog or mist

D) Clear ice

32 / 50

You are driving a large vehicle that cannot make a right turn without swinging into another lane. Which of the following figures shows the correct way to make the turn?

A) Figure C

B) Figure A

C) Figure D

D) Figure B

33 / 50

What is a tractor jackknife?

A) A device used in the hydraulic system

B) A type of trailer truck

C) A drive-wheel skid

D) Another name for hard steering

34 / 50

Which of the following is the best way to slow the vehicle when driving down a hill?

A) Downshift before the hill and keep light, continuous pressure on the brakes.

B) Shift to a higher gear.

C) Shift gears to neutral.

D) Apply heavy pressure on the brakes from time to time.

35 / 50

One of the steps in shifting up is to

A) push in the clutch and shift to the higher gear at the same time

B) release the clutch and shift to neutral.

C) press the accelerator and shift to neutral.

D) increase engine and gear speed to the RPM required.

36 / 50

Your brakes have failed on a downgrade. Using an escape ramp, downshifting and ____________________ are helpful in slowing the vehicle.

A) shifting to a higher gear

B) using the braking effect of the engine

C) using your horn

D) countersteering

37 / 50

If you must pull over to the shoulder on a major highway, you should

A) turn onto the shoulder without braking.

B) use the controlled braking method.

C) keep one set of wheels on pavement, if possible.

D) brake quickly several times to flash your brake lights.

38 / 50

To go down a long, steep hill you should

A) shift to a low gear before starting down the grade.

B) apply your brakes hard.

C) shift to a low gear after starting down the grade.

D) shift to a high gear before starting down the grade.

39 / 50

You are driving on a highway and your front tire has just blown out. You should

A) keep driving until you find a service station.

B) pump the brakes.

C) brake hard.

D) stay off the brake until you have slowed down.

40 / 50

A tie rod is part of the ________ system.

A) steering

B) brake

C) exhaust

D) suspension

41 / 50

You are driving on a rainy day and the drive wheels begin to spin. To keep control of the vehicle, which of the following is the best action to take?

A) Take your foot off the accelerator

B) Steer to the left or right

C) Accelerate slightly

D) Brake hard

42 / 50

If the radiator shutters freeze shut when driving in the winter, which of the following will occur?

A) The brakes will freeze.

B) Carbon monoxide will leak into your vehicle.

C) The engine may overheat and stop.

D) It will be harder to steer.

43 / 50

the best kind of driver is a(n) __________ one.

A) sober

B) slow

C) Offensive

D) safety first-minded and defensive

44 / 50

You are driving on slippery ice. Your rear-drive wheels lock and you begin to skid. Which of the following is the best action to take?

A) Brake hard and pull off the road.

B) Shift to neutral.

C) Take your foot off the accelerator and push the brake.

D) Take your foot off the accelerator and push in the clutch.

45 / 50

How much tread depth should you have on your front tires when driving in the winter?

A) Maximum of 2/32 inch

B) Under 4/32 inch

C) Minimum of 2/32 inch

D) Minimum of 4/32 inch

46 / 50

When backing a trailer,

A) turn the steering wheel toward the direction you want to go.

B) turn and back toward the right side.

C) use the highest reverse gear.

D) urn the steering wheel in the opposite direction you want to go.

47 / 50

What is the correct placement of warning devices when parked on the shoulder of a one-way or divided highway?

A) At 100 feet and 500 feet from the front of the vehicle

B) At 100 feet and 500 feet from the rear of the vehicle

C) At 10 feet, 100 feet, and 200 feet from the front of the vehicle

D) At 10 feet, 100 feet, and 200 feet from the rear of the vehicle

48 / 50

What are the three types of safety equipment that you must have before driving?

A) Tire-changing equipment, spare fuses, and a fire extinguisher

B) An accident reporting kit, three red reflective triangles, and tire- changing equipment

C) Spare fuses, tire chains and a fire extinguisher

D) Spare fuses, three red reflective triangles, and a fire extinguisher

49 / 50

You wish to turn left from one multilane two-way street into another multilane two-way street. Which of the figures below shows how the turn should be made?