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37 Cards in this Set
- Front
- Back
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Why should you never use the trailer handbrake to straighten out a jackknifing trailer?
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The trailer wheels caused the skid in the first place. Once the trailer wheels grip the road again, the trailer will start to follow the tractor and straighten out.******
The tractor wheels caused the skid in the first place. Once the trailer wheels grip the road again, the trailer will start to follow the tractor and straighten out. The tractor wheels caused the skid in the first place. Once the trailer wheels grip the road again, the trailer will start to push the tractor and straighten out. This is the only time that you should use the trailer brake. None of the above. |
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Why should you never use the trailer hand valve while driving?
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It should not be used in driving because the trailer brakes will not be applied evenly.
It is ok to use it while driving on dry roads. It should not be used in driving because it releases too much air from the system. It should not be used in driving because of the danger of making the trailer skid.***** |
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Large combination vehicles take longer to stop when they are fully loaded than when they are empty.
True False |
True
False****** |
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What is a bobtail?
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It is what connects the air line to the trailer.
It is the pin under the trailer that connects to the 5th wheel. It is a tractor with no trailers connected to it.**** It is another name for a dolly. |
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Large combination vehicles take longer to stop when they are empty than when they are fully loaded.
True False |
True*********
False |
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After coupling, there should be no space or gap between the upper and lower fifth wheel.
True False |
True******
False |
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Which air line carries air that is controlled by the trailer handbrake.
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Service******
Emergency |
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To drive, you need to raise the landing gear only until it just lifts off the pavement.
True False |
True
False****** |
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You push in the trailer air supply control to supply the trailer with air, and pull it out to shut the air off and put on the trailer emergency brakes.
True False |
True******
False |
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Combination vehicles are usually lighter, shorter, and require less driving skill than single commercial vehicles.
True False |
True
False***** |
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Fully loaded rigs are ten times more likely to roll over in a crash than empty rigs.
True False |
True******
False |
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What is offtracking?
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Offtracking is when the front wheels follow a different path than the front wheels.
Offtracking is when the rear wheels go into a skid and the front wheels continue in a straight line. Offtracking is when the front wheels go one direction and the trailer wheels go in the other direction. Offtracking is when the rear wheels follow a different path than the front wheels.****** None of the above. |
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Glad hands are coupling devices used to connect the service and emergency air lines from the truck or tractor to the trailer.
True False |
True*****
False |
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Combination vehicles are usually heavier, longer, and require more driving skill than single commercial vehicles.
True False |
True******
False |
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Which shut-off valves should be open and which closed?
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All shut-off valves should be closed.
All shut-off valves should be open.******* The front trailers shut-off valves open and the rear closed. The rear trailers shut-off valves open and the front closed. |
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Where are shut-off valves located?
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At the front of each trailer.
At the back of each trailer.****** At the front and back of each trailer. On the back of the tractor. |
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If the front trailer shut-off valves closed, and the rear trailer shut-off valves are open, you will hear air flowing out of the rear trailer shut-off valves.
True False |
True
False****** |
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Charge the trailer air brake system and check that the trailer rolls freely. Then stop and pull out the trailer air supply control valve. Pull gently on the trailer with the tractor to check that the trailer emergency brakes are on.
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This is not a test.
This is how can you test the tractor protection valve. This is how can you test the trailer emergency brakes.******** This is how can you test that air flows to all trailers. This is how can you test the trailer service brakes. |
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The trailer hand valve should be used only as a supplement to the engine braking effect.
True False |
True
False****** |
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Shut-off valves can be found at the front and back of each trailer.
True False |
True
False******** |
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After coupling, how much space should be between the upper and lower fifth wheel?
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1/32 inch.
1/16 inch. 1/8 inch. 1/4. None of the above.****** |
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The emergency air line supplies air to the trailer air tanks and controls the service brakes on combination vehicles.
True False |
True
False***** |
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Which air line carries air to the trailer air tanks.
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Service
Emergency****** |
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What might happen if the trailer is too high when you try to couple?
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It may not couple correctly
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Check for normal air pressure, release the parking brakes, move the vehicle forward slowly, and apply trailer brake with the hand control trolley valve, if so equipped.
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This is how can you test the tractor protection valve.
This is how can you test the trailer emergency brakes. This is how can you test that air flows to all trailers. This is how can you test the trailer service brakes.**** This is not a test. |
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What two things are most important to prevent a rollover?
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Evenly loaded trailer and properly inflated tires.
Keeping the cargo as close to the ground as possible and driving slowly around turns.***** The weight and length of the vehicle. Keeping the cargo center of gravity as high as possible and drive slowly around turns. None of the above. |
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When you turn suddenly while pulling double trailers, which trailer is most likely to turn over?
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The front trailer.
The rear trailer.**** Both trailers. Neither trailer is more likely to turn over. None of the above. |
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The trailer hand valve should be used only to test the trailer brakes.
True False |
True*****
False |
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You should look into the back of the fifth wheel to see if it is locked onto the kingpin.
True False |
True*****
False |
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Which air line carries air that is controlled by the foot brake.
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Service******
Emergency |
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Combination vehicles and the rearward amplification each trailer has after a quick lane change is reffered to as what?
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Crack the road effect.
Crack the whip effect.****** The trailer effect. The new driver effect. |
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Which of the following best describes what the trailer air supply control does.
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You pull it out to supply the trailer with air, and push it in to shut the air off and put on the trailer emergency brakes.
You push it in to supply the tractor with air, and pull it out to supply the trailer with air. You push it in to supply the trailer with air, and pull it out to shut the air off and put on the trailer emergency brakes.******** You push it in to supply the trailer with air, and pull it out to supply the tractor with air. |
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Why should you use tire chocks when parking a trailer without spring brakes?
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If the air supply in the service air tank has leaked away there will be no emergency brakes enabling the trailer wheels to turn freely.
If the air supply in the trailer air tank has leaked away there will be no emergency brakes enabling the trailer wheels to turn freely. If the air supply in the trailer air tank has leaked away there will be no emergency brakes enabling the tractor wheels to turn freely.******* If the air supply in the trailer air tank has leaked away there will be no service brakes enabling the trailer wheels to turn freely. |
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What is the emergency air line for?
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It supplies air to the tractor air tanks and controls the service brakes on combination vehicles.
It supplies air to the trailer air tanks and controls the service brakes on combination vehicles. It supplies air to the trailer air tanks and controls the emergency brakes on combination vehicles. It supplies air to the tractor air tanks and controls the emergency brakes on combination vehicles.*** None of the above. |
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Describe what the service line is for.
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It carries air which is controlled by the foot brake or the trailer handbrake.
It carries air which is controlled by the foot brake. It carries air which is controlled by the the trailer handbrake. All of the above.******* None of the above. |
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Go to the rear of the rig. Open the emergency line shut-off valve at the rear of the last trailer. You should hear air escaping, showing the entire system is charged. Close the emergency line valve. Open the service line valve to check that service pressure goes through all the trailers (this test assumes that the trailer handbrake or the service brake pedal is on), then close the valve. If you do NOT hear air escaping from both lines, check that the shut-off valves on the trailer(s) and dolly(s) are in the OPEN position.
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This is how can you test the tractor protection valve.
This is how can you test the trailer emergency brakes. This is how can you test that air flows to all trailers.****** This is how can you test the trailer service brakes. This is not a test. |
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Charge the trailer air brake system and push the air supply knob in. Shut the engine off. Step on and off the brake pedal several times to reduce the air pressure in the tanks. The trailer air supply control should pop out when the air pressure falls into the pressure range specified by the manufacturer.
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This is how can you test the tractor protection valve.********
This is how can you test the trailer emergency brakes. This is how can you test that air flows to all trailers. This is how can you test the trailer service brakes. This is how you test the air pressure gauge. None of the above. |
