CDL Practice Test


Idaho! You will be presented with 40 questions and you must answer 34 questions correctly to pass.  There is a 50 minute time limit.  You may not go back once you answer a question.  Click the "Start Test" button below to begin.  Good luck!

1 / 40

Overhead inside mirror is used to:

2 / 40

Which seats must have a seat belt:

3 / 40

Urban mass transit coaches may have a brake and accelerator interlock system. Which of the following statements is true?

4 / 40

To prevent a roll over a driver can 1) keep the cargo as low to the ground as possible and 2) _____.

5 / 40

If you have riders on board, you must never refuel:

6 / 40

The cause of almost half of all truck driver deaths are:

7 / 40

At a railroad crossing, the bus is required to stop at the stop line. If there is no clearly marked stop line, what is the required minimum and maximum stopping distance?

8 / 40

In Column 1 the symbol "I" means:

9 / 40

Which of the following statements about loading and unloading cargo tanks is false?

10 / 40

What should you check for when inspecting a converter dolly?

11 / 40

A shipper’s certification is best described as _____.

12 / 40

On a drawbridge, you do not need to stop, but must slow down and make sure it's safe, when:

13 / 40

If you are driving a 100-foot truck with double trailers at 30 mph in dry conditions, how many seconds of space should there be between your truck and other vehicles?

14 / 40

Select the part that is not a part of the drum brake:

15 / 40

Some school busses are marked with the LNG placard. What does LNG stand for?

16 / 40

Which contains more alcohol: a 12-ounce glass of 5% beer, a 5-ounce glass of 12% wine or a 1 1/2-ounce shot of 80 proof liquor?

17 / 40

What is NOT one of the four skill areas that operating a commercial vehicle requires?

18 / 40

A placarded vehicle must carry what type of fire extinguisher?

19 / 40

What are spring brakes?

20 / 40

Select the true statement about baffled tankers:

21 / 40

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

22 / 40

You downshift automatic transmissions ______.

23 / 40

A driver of a tank vehicle should take curves, off ramps, and on ramps at a speed lower than the posted speed limit.

24 / 40

While driving on a clear night with low beam headlights, you should be able to stop within:

25 / 40

Why is understanding the loading and unloading procedures so critical?

26 / 40

How do you test the trailer service brakes?

27 / 40

When accelerating:

28 / 40

What is the value of the overhead rear-view mirror inside of the bus?

29 / 40

Remember to____when connecting the converter dolly to the rear trailer.

30 / 40

You should look into the back of the fifth wheel on a dolly to see if it is locked onto the kingpin.

31 / 40

Which of the following statements about "Radioactive" labels is true?

32 / 40

Select what you should do before leaving the vehicle unattended:

33 / 40

When using turn signals, which of the following should be avoided?

34 / 40

These tires should have a minimum tread depth of 4/32 inches.

35 / 40

If students must cross the street, when they get off the bus, which statement is true?

36 / 40

Buses may NOT have recapped or regrooved tires:

37 / 40

Select the true statement about seeing ahead.

38 / 40

The school bus driver may be the only contact person from school system some parents meet. The percentage of such parents is as high as:

39 / 40

When transporting both hazardous and non hazardous materials, your bills must:

40 / 40

The golden rule for school buses when approaching and crossing railroad tracks is:

Your score is

The average score is 72%

5/5 - (2 votes)

CDL Category Practice Tests

CDL Practice Test

How To Get A idaho Commercial Drivers License

Applicants can be age 18 or older when applying for their CDL. Those under the age of 21 are not eligible for the Hazmat or Doubles/Triples Endorsement. All applicants must get a DOT medical card to shows their ability to be physically able to drive a commercial motor vehicle.

Any drivers that fall into the following categories are disqualified from receiving their CDL:

  • Having more than one driver’s license.
  • Being convicted of an impaired driving offense in a commercial vehicle within the prior 24 months to submitting the CDL application.
  • Current suspended, revoked, denied, or canceled driver’s license.
  • Having CDL disqualifications in other states.

All applicants are required to complete a practical skills test and knowledge test in order to receive their CDL. Adding endorsements to a CDL will require additional knowledge tests and practical skills tests.

T – Doubles / Triples
P – Passenger
N – Tank Vehicles
H – Hazardous Materials
X – Tank Vehicle That Carries Hazardous Materials

Hit the Open Road

idaho CDL License Test Tips

Applicants for an Idaho CDL must complete a written knowledge test to showcase their retention of the commercial driving laws. Class A drivers are required to take a 70 question assessment that includes 20 questions specifically about combination vehicles. Class B and C applicants are required to pass a 50 question assessment. Those seeking endorsements and removal of the Air Brake Restriction must take additional tests that range between 20 and 30 questions. All tests must be passed with a score of 80 percent or better.

CDL applicants are required to pass a three-part skills test. These parts include a driving test, basic control skills test, and vehicle inspection test. This can be completed at an Idaho State Driving Facility or other approved testing site.

Additional Information

Information on the Idaho Transportation Department

The Idaho Transportation Department administers the CDL requirements and testing in Idaho. To get more information contact them via:


Phone:  208.334.8000


Additional Idaho CDL Helpful Links

Please use the links below to access more valuable Idaho CDL testing resources and to learn more about practice driving tests for the state of Idaho.