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📖 Combination Test
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31
When connecting the glad hands press the two seals with the coupler together at what degree to each other?
45 degree.
90 degree. ✓ CORRECT
180 degrees.
32
Which of these statements is true?
The brakes and suspension systems of combination vehicles work best with a light load.
Light vehicles need more braking power to stop than heavy ones.
Bobtail tractor can take longer to stop than a combination vehicle loaded to maximum gross weight. ✓ CORRECT
33
Why should you lock the tractor glad hands to each other ( or dummy couplers) when you are not towing trailer?
The connected brake circuit becomes a back up air tank.
It will keep dirt or water out of the lines. ✓ CORRECT
If you didn’t, you could never build system pressure.
34
When backing a tractor under a trailer you should:
Always use to lowest reverse gear. ✓ CORRECT
Always approach the trailer at a slight angle.
Do it quickly to ensure that the kingpin is locked into the fifth wheel.
35
After the trailer has been coupled to the tractor, the tractor protection control valve should be placed in what position?
Down.
Up.
Normal. ✓ CORRECT
36
The fifth wheel locking lever is not locked after the jaws close around the kingpin. This means that:
The trailer will not swivel on the fifth wheel.
The parking lock is off and you may drive away.
The coupling is not right and should be fixed before driving the coupled unit. ✓ CORRECT
37
Off-tracking or cheating causes of which of these to follow the wider pass while making a turn?
Tractor towing a 45-feet trailer. ✓ CORRECT
Tractor with two 27-feet trailers.
53-feet bobtail.
38
The iron trailer supports are up and the trailer is resting on the tractor. Make sure:
There is enough clearance between the upper and lower fifth wheels.
The safety latch is in unlocked position.
There is enough clearance between the tractor frame and the landing gear. ✓ CORRECT
39
When you are uncoupling a loaded trailer you should lower the landing gear until it:
Make firm contact with the ground, then crackly hits a low gear a few turns. ✓ CORRECT
Make contact with the ground and leave the trailer off the fifth wheel.
Reaches the ground.
40
When you are uncoupling a loaded trailer you should lower the landing gear until it:
Make firm contact with the ground, then crackly hits a low gear a few turns. ✓ CORRECT
Make contact with the ground and leave the trailer off the fifth wheel.
Reaches the ground.