This CDL general knowledge practice test will examine your knowledge of general trucking, safe transportation of cargo, safe driving, and the correct way to perform a pre-trip vehicle inspection. In order to receive your CDL, it is required that you pass the state’s official CDL General Knowledge exam.

General Knowledges Test 01

1 / 30

Every major groove on the front tires of a commercial vehicle must have a tread depth of at least?

2 / 30

To check the stopping action of your service brakes, you should test them at about...?

3 / 30

What is the proper color at the front of a vehicle for parking, clearance and identification lights?

4 / 30

As part of your safety equipment, your vehicle should have how many red reflective triangles?

5 / 30

If your oil pressure is below the indicated limit, you should...?

6 / 30

If you are transporting a cargo you must inspect its securement within what distance of starting a trip?

7 / 30

If a yellow light on the left rear of the trailer stays on when you switch the engine on, this means...?

8 / 30

If lock nuts on your wheels have streaks of rust, this may indicate...?

9 / 30

On a 20 inch steering wheel, there should not be more than how much play?

10 / 30

What paperwork should you check before beginning your pretrip inspection?

11 / 30

If your vehicle has hydraulic brakes, you should pump the brake pedal three times and then apply firm pressure for five seconds. The pedal should...?

12 / 30

Front facing turn signals must be what color?

13 / 30

Air pressure for your brakes should build from 50 to 90 psi within what time?

14 / 30

When you are on the road, you must fasten your seatbelt...?

15 / 30

Wheels or rims are unsafe if they have been welded...?

16 / 30

Rear turn signals should be which of these colors?

17 / 30

The second step of a pretrip inspection should be to check...?

18 / 30

As you check your signal lights, you should...?

19 / 30

What is the main problem which a broken exhaust system can cause?

20 / 30

After your first in trip inspection of the securement of your cargo, you must make regular additional inspections...?

21 / 30

Why should you look under your vehicle at the beginning of your pretrip inspection?

22 / 30

The most important reason for inspecting your vehicle before traveling is...?

23 / 30

All tires other than the front tires of a commercial vehicle must have a minimum tread depth of...?

24 / 30

Which of these is permitted for use on the front wheels of the bus?

25 / 30

Side marker reflectors which are not at the rear of the vehicle must be what color?

26 / 30

Side marker lights must be what color at the rear of the vehicle?

27 / 30

When checking the steering system, it must be tested...?

28 / 30

A vehicle must be placed out of service if what fraction of the leaves in any spring assembly on the suspension are broken?

29 / 30

Before starting the engine on a manual vehicle you should make sure your gearshift is in...?

30 / 30

Which of these senses should be used during a trip to check for problems?

Your score is


Why Take This CDL General Knowledge Practice Test?

You will be required to take a written knowledge test (try our CDL general knowledge practice test). Once you pass this test, you will be required to drive with another CDL licensed driver and practice driving on the road for at least 14 days.

The cost of getting your CDL will vary depending on the state you live in. On average, obtaining a learner’s permit will cost around $25. To get your full CDL license, fees will range from $50 to $200. While this might seem like a lot of money, the income you will receive in the future will make it worth the money.

There are three types of CDL classes that determine the type of vehicle you may drive and how much you may tow. A Class A CDL class allows you to operate a vehicle with a GCWR of 26,001 if the vehicle you tow weighs more than 10,000 and a Class B CDL allows you to operate a vehicle with a GVWR of 26,001 or more pounds or operate any vehicle towing another vehicle that weighs less than 10,000 GVWR. With a Class C CDL, you can operate a Class C vehicle that transports hazardous materials.