CDL Combination
Vehicles Test

3

This is the Commercial Vehicle Driver's License Test covering Combination Vehicles.  You will be presented with 40 questions and you must answer 34 questions correctly to pass.  There is no time limit.  You may not go back once you answer a question.  Click the "Start Quiz" button below to begin.  Good luck!

1 / 40

Off-tracking happens when going around a corner and:

2 / 40

Make sure____when the front trailer supports are up and the trailer is sitting on the tractor.

3 / 40

Select the portion of the combination vehicle that is most likely to turn over suddenly when pulling a double trailer:

4 / 40

What should you do before you begin to couple?

5 / 40

How should the hand valve be used?

6 / 40

What position should the tractor protection control valve be in after coupling?

7 / 40

Is it important to look into the back of the fifth wheel to see if the lockpin is locked in?

8 / 40

How do you supply air to the trailer tanks?

9 / 40

Before backing under the trailer after connecting the air lines you should:

10 / 40

Select the true statement in regards to crossing your air lines on a new trailer with spring brakes

11 / 40

The locking jaws of the kingpin should close around:

12 / 40

What should you do if you start a trailer skid?

13 / 40

Select the situation in which you should use the hand valve to park a combination vehicle.

14 / 40

What might happen if a trailer is too high when you try to couple?

15 / 40

The purpose for the emergency air line is:

16 / 40

Select the vehicle that off-tracks the most.

17 / 40

How should the hand valve be used?

18 / 40

How should the trailer be lined up when preparing to back the tractor up?

19 / 40

Select the true statement:

20 / 40

What will happen right away should the service air line come apart but the emergency line is intact while driving a combination vehicle?

21 / 40

Select the definition of "off-tracking."

22 / 40

Select the statement that best describes what the trailer air supply control does:

23 / 40

If you park the trailer at an angle to the tractor when uncoupling:

24 / 40

You must first______to supply air to the trailer.

25 / 40

Make sure that_____before you back under a trailer.

26 / 40

What is the service air line controlled by?

27 / 40

What will happen should a driver cross the air lines when hooking up the an older trailer?

28 / 40

It is good practice to_____when uncoupling.

29 / 40

A tractor should not be backed under a trailer until the whole air system is:

30 / 40

To test the security of the tractor semi trailer connection you should:

31 / 40

When should the trailer hand valve be used?

32 / 40

Select the step that comes first:

33 / 40

Why should you not use the trailer hand brake to straighten out a jackknifing trailer?

34 / 40

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

35 / 40

Select when you should use the hand valve to park a combination vehicle.

36 / 40

Select the reason as to why you should not use the trailer hand valve while driving.

37 / 40

When driving a combination vehicle, the trailer breaks away severing the air lines. The trailer brakes should come on and ____.

38 / 40

Before backing under the trailer you should______when coupling a tractor and trailer with air lines already connected.

39 / 40

You should back up slowly until____when coupling the trailer.

40 / 40

What color and shape is the trailer air supply control?

Your score is

The average score is 70%

5/5 - (3 votes)

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