CDL Combination Test Solved
"Off-tracking" occurs when you go around a corner and: - ANSWER-The rear wheels
follow a different path than the front wheels
A device which connects the service and emergency air lines from the truck to the trailer is
called.. - ANSWER-Glad hands
A king pin is: - ANSWER-A pin which locks the trailer to the tractor on the fifth wheel
After you connect the air lines, but before you back under the trailer, you should: -
ANSWER-Supply air to the trailer system, then pull out the air supply knob
After you have coupled the trailer you should raise the landing gear by using: - ANSWER-
Low gear
After you lock the kingpin into the fifth wheel, you should check the connection by: -
ANSWER-Pulling the tractor ahead gently with trailer brakes locked
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: - ANSWER-Applying and releasing the trailer brakes
and listening for brake sounds; and also by lifting the brake pedal
After you supply air to the trailer, make sure the airlines are not crossed and the trailer
brakes are working. This is done by: - ANSWER-Applying and releasing the trailer brakes
and listening for brake sounds
Air and electrical lines from the tractor to the trailer should be: - ANSWER-Secured but with
enough to loop the turn
Air lines on a combination vehicle are often colored to keep them from getting mixed up.
The emergency line is ____; the service line is _____. - ANSWER-Red, blue
Before you back under a trailer, make sure the: - ANSWER-Trailer brakes are locked
Before you begin coupling: - ANSWER-Check your path for hazards
Compared to a straight truck or bus there are ____ things to inspect in combination
vehicles. - ANSWER-More
Emergency controlled braking is when you: - ANSWER-Apply the brakes as hard as you
can without locking the wheels
How much space should there be between the upper and lower fifth wheel after coupling? -
ANSWER-none
, How should you test the tractor semitrailer connection for security? - ANSWER-Pull gently
forward against the locked trailer brakes then look at it carefully
If one of the glad hands on your blue air line is missing a seal: - ANSWER-You might end
up with a service line air leak
If one of the glad hands on your blue air line is missing a seal: - ANSWER-You might end
up with a service line air leak
If the brakes are not released when you pushed the trailer air supply valve you should: -
ANSWER-Check air line connection
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 - ANSWER-Nothing is likely to
happen until you try to apply the brakes
If you cannot make a turn without entering another lane, you should: - ANSWER-Turn wide
before you start your turn
If you cross air lines on a new trailer with spring brakes: - ANSWER-You won't be able to
release the trailer brakes
If you cross connect the two air lines the following will result - ANSWER-You will not have
air going to the trailer brakes
If you start a trailer skid you should: - ANSWER-Release the brakes to get traction back
In general, the higher your trucks "center of gravity" the: - ANSWER-easier it is to turn over
In normal driving, some drivers use the hand valve before applying the brake pedal to
prevent a jackknife. Which of these statements is true? - ANSWER-It should not be done
In order to inspect the coupling, you should: - ANSWER-Use a flashlight if necessary
In order to supply air to the trailer, you must first: - ANSWER-Stop engine so you can hear
the brakes
Large combination vehicles take longer to stop: - ANSWER-When they are empty
Off-tracking or cheating causes which of these to follow the wider path while making a
turn? - ANSWER-Tractor towing a 45 feet trailer
Th trailer air supply control: - ANSWER-Is a red, eight sided knob
"Off-tracking" occurs when you go around a corner and: - ANSWER-The rear wheels
follow a different path than the front wheels
A device which connects the service and emergency air lines from the truck to the trailer is
called.. - ANSWER-Glad hands
A king pin is: - ANSWER-A pin which locks the trailer to the tractor on the fifth wheel
After you connect the air lines, but before you back under the trailer, you should: -
ANSWER-Supply air to the trailer system, then pull out the air supply knob
After you have coupled the trailer you should raise the landing gear by using: - ANSWER-
Low gear
After you lock the kingpin into the fifth wheel, you should check the connection by: -
ANSWER-Pulling the tractor ahead gently with trailer brakes locked
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: - ANSWER-Applying and releasing the trailer brakes
and listening for brake sounds; and also by lifting the brake pedal
After you supply air to the trailer, make sure the airlines are not crossed and the trailer
brakes are working. This is done by: - ANSWER-Applying and releasing the trailer brakes
and listening for brake sounds
Air and electrical lines from the tractor to the trailer should be: - ANSWER-Secured but with
enough to loop the turn
Air lines on a combination vehicle are often colored to keep them from getting mixed up.
The emergency line is ____; the service line is _____. - ANSWER-Red, blue
Before you back under a trailer, make sure the: - ANSWER-Trailer brakes are locked
Before you begin coupling: - ANSWER-Check your path for hazards
Compared to a straight truck or bus there are ____ things to inspect in combination
vehicles. - ANSWER-More
Emergency controlled braking is when you: - ANSWER-Apply the brakes as hard as you
can without locking the wheels
How much space should there be between the upper and lower fifth wheel after coupling? -
ANSWER-none
, How should you test the tractor semitrailer connection for security? - ANSWER-Pull gently
forward against the locked trailer brakes then look at it carefully
If one of the glad hands on your blue air line is missing a seal: - ANSWER-You might end
up with a service line air leak
If one of the glad hands on your blue air line is missing a seal: - ANSWER-You might end
up with a service line air leak
If the brakes are not released when you pushed the trailer air supply valve you should: -
ANSWER-Check air line connection
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 - ANSWER-Nothing is likely to
happen until you try to apply the brakes
If you cannot make a turn without entering another lane, you should: - ANSWER-Turn wide
before you start your turn
If you cross air lines on a new trailer with spring brakes: - ANSWER-You won't be able to
release the trailer brakes
If you cross connect the two air lines the following will result - ANSWER-You will not have
air going to the trailer brakes
If you start a trailer skid you should: - ANSWER-Release the brakes to get traction back
In general, the higher your trucks "center of gravity" the: - ANSWER-easier it is to turn over
In normal driving, some drivers use the hand valve before applying the brake pedal to
prevent a jackknife. Which of these statements is true? - ANSWER-It should not be done
In order to inspect the coupling, you should: - ANSWER-Use a flashlight if necessary
In order to supply air to the trailer, you must first: - ANSWER-Stop engine so you can hear
the brakes
Large combination vehicles take longer to stop: - ANSWER-When they are empty
Off-tracking or cheating causes which of these to follow the wider path while making a
turn? - ANSWER-Tractor towing a 45 feet trailer
Th trailer air supply control: - ANSWER-Is a red, eight sided knob
