NC CDL Combination Vehicles Exam
NC CDL Combination Vehicles Exam
Graded A 2024
You are coupling a semi-trailer to your tractor but have not yet backed under, the trailer
is at the right height when: - It will be raised slightly when the tractor is backed under it.
You should not back a tractor under a trailer until the whole air system is: - At normal
pressure.
Which part of the kingpin should the locking jaws close around? - The shank.
When you get ready to back under the semi-trailer you should line up: - Directly in front
of the trailer.
How should you test the tractor semi-trailer connection for security? - Pull gently forward
in low gear against the locked trailer brakes, then look at it carefully.
When should you use the hand valve to park a combination vehicle? - Never.
You supply air to the trailer tanks by: - Pushing in the trailer air supply valve.
Why should you be sure that the fifth wheel plate is greased as required? - To prevent
steering problems.
After you supply air to the trailer, make sure the air lines are not crossed and the trailer
brakes are working. This is done by: - Applying and releasing the trailer brakes and
listening for brake sounds.
There are two things that a driver can do to prevent a rollover. They are: (1) Keep the
cargo as close to the ground as possible; and (2): - Go slowly around turns.
NC CDL Combination Vehicles Exam
, NC CDL Combination Vehicles Exam
Before you back under a trailer, make sure the: - Trailer brakes are locked.
If the service air line comes apart while you are driving a combination vehicle, but the
emergency line stays together, what will happen right away? - Nothing is likely to
happen until you try to apply the brakes.
The air leakage rate for a combination vehicle (engine off, brakes on) should not be
more than ___ PSI per minute. - 4
In normal driving, some drivers use the hand valve before applying the brake pedal to
prevent a jackknife. Which of these statements is true? - If the trailer has not spring
brakes, you can drive away, but you will not have trailer brakes.
Why should you lock the tractor glad hands (or dummy couplers) to each other when
you are not towing a trailer? - It will keep dirt and water out of the lines.
For coupling to be completed, the safety catch for the fifth wheel locking lever must be: -
Over the locking lever.
The front trailer supports are up and trailer is resting on the tractor. Make sure: - There
is enough clearance between the tractor frame and the landing gear.
You have a major leak in the service line and you put on the brakes. Service air
pressure will escape and cause the: - Trailer emergency brakes to come on.
When backing under a tractor under a trailer you should expect: - Trailer will be lifted
slightly when the tractor backs under it.
The driver crosses the air lines when hooking up to an old trailer. What will happen? - If
the trailer has no spring brakes, you can drive away, but you will not have trailer brakes.
NC CDL Combination Vehicles Exam
NC CDL Combination Vehicles Exam
Graded A 2024
You are coupling a semi-trailer to your tractor but have not yet backed under, the trailer
is at the right height when: - It will be raised slightly when the tractor is backed under it.
You should not back a tractor under a trailer until the whole air system is: - At normal
pressure.
Which part of the kingpin should the locking jaws close around? - The shank.
When you get ready to back under the semi-trailer you should line up: - Directly in front
of the trailer.
How should you test the tractor semi-trailer connection for security? - Pull gently forward
in low gear against the locked trailer brakes, then look at it carefully.
When should you use the hand valve to park a combination vehicle? - Never.
You supply air to the trailer tanks by: - Pushing in the trailer air supply valve.
Why should you be sure that the fifth wheel plate is greased as required? - To prevent
steering problems.
After you supply air to the trailer, make sure the air lines are not crossed and the trailer
brakes are working. This is done by: - Applying and releasing the trailer brakes and
listening for brake sounds.
There are two things that a driver can do to prevent a rollover. They are: (1) Keep the
cargo as close to the ground as possible; and (2): - Go slowly around turns.
NC CDL Combination Vehicles Exam
, NC CDL Combination Vehicles Exam
Before you back under a trailer, make sure the: - Trailer brakes are locked.
If the service air line comes apart while you are driving a combination vehicle, but the
emergency line stays together, what will happen right away? - Nothing is likely to
happen until you try to apply the brakes.
The air leakage rate for a combination vehicle (engine off, brakes on) should not be
more than ___ PSI per minute. - 4
In normal driving, some drivers use the hand valve before applying the brake pedal to
prevent a jackknife. Which of these statements is true? - If the trailer has not spring
brakes, you can drive away, but you will not have trailer brakes.
Why should you lock the tractor glad hands (or dummy couplers) to each other when
you are not towing a trailer? - It will keep dirt and water out of the lines.
For coupling to be completed, the safety catch for the fifth wheel locking lever must be: -
Over the locking lever.
The front trailer supports are up and trailer is resting on the tractor. Make sure: - There
is enough clearance between the tractor frame and the landing gear.
You have a major leak in the service line and you put on the brakes. Service air
pressure will escape and cause the: - Trailer emergency brakes to come on.
When backing under a tractor under a trailer you should expect: - Trailer will be lifted
slightly when the tractor backs under it.
The driver crosses the air lines when hooking up to an old trailer. What will happen? - If
the trailer has no spring brakes, you can drive away, but you will not have trailer brakes.
NC CDL Combination Vehicles Exam
