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

Select the true statement in regards to what the fifth wheel should be checked for.

2 / 40

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

3 / 40

How do you make sure the air lines are not crossed and the trailer brakes are working after supplying air to the trailer?

4 / 40

How high should you crank the landing gear?

5 / 40

You should have the fifth wheel plate greased as recommened because:

6 / 40

How should the hand valve be used?

7 / 40

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

8 / 40

Select the answer that is controlled by the foot brake.

9 / 40

Off-tracking happens when going around a corner and:

10 / 40

The air leakage rate for combination vehicles should not be more than _ psi a minute.

11 / 40

Select the definition of "off-tracking."

12 / 40

You should line up_____when getting ready to back under the trailer.

13 / 40

Make sure that____when the front trailer supports are up and the trailer is resting on the tractor.

14 / 40

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

15 / 40

What should you do if you start a trailer skid?

16 / 40

The emergency air line is used to:

17 / 40

Select the two things that are important in preventing a rollover:

18 / 40

Why should you use chocks when parking a trailer without spring brakes?

19 / 40

Where should the safety catch for the fifth wheel locking lever be located for coupling to be complete?

20 / 40

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

21 / 40

Select the vehicle that off-tracks the most.

22 / 40

The air leakage rate for a combination vehicle should not exceed ____psi a minute.

23 / 40

Select the statement that describes how you could damage the landing gear.

24 / 40

Select what you should not do when coupling the glad hands.

25 / 40

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

26 / 40

Select the accurate statement in regards to rolling up the landing gear to complete the coupling process.

27 / 40

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

28 / 40

Select the true statement in regards to as why you should make sure the fifth wheel plate is greased as recommended:

29 / 40

How should the hand valve be used?

30 / 40

When driving normally, some drivers use the hand valve before applying the brake pedal to prevent jack knifing. Select the most appropriate response to this statement.

31 / 40

You should____in order to inspect the coupling.

32 / 40

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

33 / 40

When should the trailer hand valve be used?

34 / 40

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

35 / 40

______is a device that connects the service and emergency air lines between the tractor and trailer.

36 / 40

Select the false statement about tractor protection valves.

37 / 40

When you have a major leak in the service line and put on the brake, the service air pressure will escape and cause the:

38 / 40

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

39 / 40

What color and shape is the trailer air supply control?

40 / 40

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

Your score is

The average score is 70%

5/5 - (3 votes)

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