Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CDL-Class > 2.of.3 - CDL Prep - App Air Brakes > Flashcards

2.of.3 - CDL Prep - App Air Brakes Flashcards

CDL Prep - App

1
Q

Question:
1. During normal driving, spring brakes are usually held back by?

  • Air pressure.
  • Spring pressure.
  • Bolts of clamps.
A

Air pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Question:
2. Under normal conditions, in order to engage the parking brakes, the driver should?

  • Apply brakes by pulling the parking brake control knob out.
  • Be sure air brakes systems is fully pressurized.
  • Turn off the engine.
A

Apply brakes by pulling the parking brake control knob out.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Question:
3. With air brake vehicles, the parking brake should be used?

  • Whenever you leave the vehicle unattended.
  • Only during pre-trip inspections.
  • As little as possible.
A

Whenever you leave the vehicle unattended.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Question:
4. Excessive use of the service brakes results in overheating, which can lead to?

  • Increase contact between the brake drums and linings.
  • Expansion of the brake drums.
  • Proper adjustment of S-Cam.
A

Expansion of the brake drums

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Question:
5. A straight truck or bus air brake system should not leak at the rate of more than ____ psi per minute with the engine off and the brakes released?

  • 1.
  • 2.
  • 3.
A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Question:
5. The brake pedal in an air brake system?

  • Controls the air pressure applied to the brakes?
  • Is connected to slack adjusters by a series of rods and linkages.
  • Controls the speed of the air compressor.
A

Controls the air pressure applied to the brakes?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Question:
7. If your truck or bus has dual parking control valves, you can use pressure from a separate tank to?

  • Release the spring emergency/parking brakes to move a short distance.
  • Stay parked twice as long without using up service air pressure.
  • Balance the service brake system when you are parked.
A

Release the spring emergency/parking brakes to move a short distance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Question:
8. What happens when your brake drums very hot?

  • They start to smoke.
  • They contract.
  • They expand.
A

They expand.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Question:
9. The safety valve reduces pressure at ____ psi?

  • 50.
  • 100.
  • 150.
A

150.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Question:
10. Total stopping distance for air brakes is longer than that for hydraulic brakes due to ______ distance?

  • Brake lag.
  • Effective braking.
  • Reaction.
A

Brake lag.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Question:
11. The supply pressure gauge shows how much pressures?

  • Is in the air tanks.
  • Is going to the brake chamber.
  • You have used in this trip.
A

Is in the air tanks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Question:
12. The most important thing to do when a low air pressure warning comes on is?

  • Up-shift
  • Downshift.
  • Stop and safely park as soon as possible.
A

Stop and safely park as soon as possible.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Question:
13. When brake are applied, the brake shoes will press against the?

  • Brake drum or disc.
  • S-Cam.
  • Slack adjuster.
A

Brake drum or disc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Question:
14. The stop light switch?

  • Turns on the brake lights when you put on the air brakes.
  • Tells you when the air brake system is low on air pressure.
  • Tells you when you need yo use your emergency brakes.
A

Turns on the brake lights when you put on the air brakes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Question:
The proper use of the brakes when going down a long steep grade after selecting a proper gear ____ below the posted speed and release your brake?

  • 10 mph.
  • 15 mph.
  • 5 mph.
A

5 mph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Question:
16. Why should you drain water from compressed air tanks?

  • Water low boiling point reduces braking power.
  • To keep from fowling the air compressor oil.
  • Water can freeze in cold weather and cause brake failure.
A

Water can freeze in cold weather and cause brake failure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Question:
17. Your truck or bus has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?

  • Reduce your speed and drive to the nearest garage for repairs.
  • Reduce your speed and test the remaining system while under way.
  • Stop right away and safely park. Continue only after the system is fixed.
A

Stop right away and safely park. Continue only after the system is fixed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Question:
18. A slack adjusted if it is more than about ________ when you pull hard on it?

  • 1/4 inch.
  • 1 inch.
  • 1/2 inch.
A

1 inch.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Question:
19. The use of brakes on a long and steep downgrade under normal conditions is only a supplement to?

  • The use of the front brake limiting valve.
  • The braking effect of the engine.
  • Use of spring brakes.
A

The braking effect of the engine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Question:
20. If your vehicle has alcohol evaporator, it is there to?

  • Boost tank pressure, the same way that turbocharges boost engine.
  • Reduce the risk of icing in air brake valves in cold weather.
  • Eliminate need for daily tank draining.
A

Reduce the risk of icing in air brake valves in cold weather.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Question:
21. An air brake system is fully charged at what psi?

  • 125.
  • 100.
  • 75.
A

125.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Question:
22. What can legally hold a parking or emergency brake in position for a truck, truck tractor, or bus?

  • Fluid pressure.
  • Air pressure.
  • Spring pressure.
A

Spring pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The braking power of the springs brakes?

  • Can only be tested by highly trained brake service people.
  • Is not affected by the condition of the service brakes.
  • Depends on the brakes being in adjustment.
A

Depends on the brakes being in adjustment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Question:
24. Air brakes takes more time than hydraulic braking because.

  • Air brakes take more time to flow through the lines than hydraulic fluid.
  • Air brakes require heavies return springs.
  • Air brakes use different brake drums.
A

Air brakes take more time to flow through the lines than hydraulic fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Question:
25. The S-cam?

  • Pulls the brake shoes away from the drum and allow the wheels to roll freely.
  • Controls the air flow to each of the brake chambers.
  • Forces the brake shoes against the inside of the brake drum.
A

Forces the brake shoes against the inside of the brake drum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Question:
26. The driver must be able to see a low air pressure warning which comes on before pressure in the service air tanks falls below _____ psi?

  • 80.
  • 40.
  • 60.
A

60.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Question:
27. The air brake lag distance at 55 mph on dry pavement adds about _____ feet?

  • 32.
  • 52.
A

32.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Question:
28. Repeatedly partially increasing and pressing the brake pedal may result in?

  • A buildup of brake air pressure.
  • No change of brake air pressure.
  • A loss of brake air pressure.
A

A loss of brake air pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Question:
29. If the spring brakes are on, when should you push the brake pedal?

  • Only on a slippery road.
  • Never.
  • Only when driving downhill.
A

Never.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Question:
30. Excessive heat caused by using your brakes too often can also cause?

  • Brake to fade or fail.
  • Brake linings to split up.
  • Modulate control valve to wear out.
A

Brake to fade or fail.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Question:
31. If you must make an emergency stop, you should brake so you?

  • Use the hand brake first.
  • Can steer and keep your vehicle in a straight.
  • Can steer hard while braking hard.
A

Can steer and keep your vehicle in a straight.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Question:
32. If your vehicle has an alcohol evaporator, every day during cold weather you should?

  • Check the oil for alcohol content.
  • Check an fill the alcohol level.
  • Change the alcohol from a bottle.
A

Check an fill the alcohol level.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Question:
33. Parking or emergency brake of trucks and buses can be legally held on by _____ pressure?

  • Fluid.
  • Air.
  • Spring.
A

Spring.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Question:
34. In ideal condition, a truck or bus with air brakes going at 55 mph would require the stopping distance of how many feet?

  • From 100 to 300 feet.
  • Less than 100 feet.
  • More than 300 feet.
A

More than 300 feet.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Question:
35. All air brake-equipped vehicles have:

  • A backup hydraulic system.
  • An air usage gauge.
  • A supply pressure gauge.
A

A supply pressure gauge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Question:
36. The application pressure gauge shows how much air pressure you?

  • Are applying to the brakes.
  • Have in a modulating control valve.
  • Have in the air tanks.
A

Are applying to the brakes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Question:
37. The air compressor stop pumping air at what psi?

  • 150.
  • 100.
  • 125.
A

125.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Question:
38. The most common type of foundation brake found on heavy vehicles is the?

  • Disc
  • Wedge drum.
  • S-cam drum.
A

S-cam drum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Question:
39. The air loss rate for a straight truck or bus with the engine off and the brakes on should not be more than?

  • 1 psi in 30 seconds
  • 3 psi in one minute
  • 2 psi in 45 seconds
A

3 psi in one minute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Question:
41. It is accepted that too much heat caused by using your brakes too often can also cause?

  • Brake linings to split up.
  • Brake to fade of fail.
  • Modulated control valve to wear out.
A

Brake to fade of fail.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Question:
41. The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away like?

  • Hydraulic pressure.
  • Spring pressure.
  • Air pressure.
A

Spring pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Question:
42. The driver must be able to see a low air pressure warning which comes on before pressure in the service air tanks falls below ______ psi?

  • 60.
  • 50.
  • 80.
A

60.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Question:
43. Some air brake systems have an alcohol evaporator. What may happen if you don’t keep the proper level of alcohol?

  • Ice may from in the air brake valves and cause brake failure.
  • The S-cam may not take back when you release the brake pedal.
  • Ice may form on the brake drums and wear them out.
A

Ice may from in the air brake valves and cause brake failure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Question:
44. If you do not have automatic thank drains, how often should you drain the oil and water from the bottom of compressed air storage thanks?

  • At the end of each day of driving.
  • After every four hours of service.
  • Once a week.
A

At the end of each day of driving.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Question:
45. The air compressor governor controls?

  • Air pressure applied to the brakes.
  • When air is pumped into the air tanks.
  • The speed of the air compressor.
A

When air is pumped into the air tanks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Question:
46. It is not safe to drive a vehicle that has brake drums with cracks that are longer than _____ of the width of the friction area?

  • 1/8.
  • 1/2.
  • 1/4.
A

1/2.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Question:
47. The _____ shows how much pressure is in the air thanks?

  • Oil gauge.
  • Air usage gauge.
  • Supply pressure gauge.
A

Supply pressure gauge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Question:
48. If air pressure is not built up within the correct amount of time, then?

  • You should be ready to use your parking brakes to stop.
  • Air pressure may drop to a low point while driving, requiring an emergency stop.
  • The alcohol container may be low.
A

Air pressure may drop to a low point while driving, requiring an emergency stop.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Question:
49. During normal driving, spring brakes are usually held back by?

  • Bolts or clamps.
  • Spring pressure.
  • Air pressure.
A

Air pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Question:
50. The spring brakes used on the chambers in a straight truck will bring you to stop when air pressure drops below _____ psi?

  • 60.
  • 20.
  • 100.
A

20.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Question:
51. If the air compressor should develop a leak, what keep the air in the tanks?

  • The one-way check valve.
  • The tractor protection valve.
  • The emergency relay valve.
A

The one-way check valve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Question:
52. The ________ shows how much pressure is in the air tanks?

  • Oil Gauge.
  • Air usage Gauge.
  • Supply pressure gauge.
A

Supply pressure gauge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Question:
53. If your vehicle has an alcohol evaporator, it is there to?

  • Eliminate the need for daily tank draining.
  • Boost thank pressure, the same way that turbocharges boost engine.
  • Reduce the risk of icing in air brake valves in cold weather.
A

Reduce the risk of icing in air brake valves in cold weather.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Question:
54. If your truck has a properly functioning dual air brake system and minimum-size air tanks, the air pressure should build up from 85 to 100 psi within how many seconds?

  • 45
  • 60
  • 30
A

45

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Question:
55. The springs brakes used on the chambers in a straight truck will bring you to stop when air pressure drops below _____ psi?

  • 100
  • 60
  • 20
A

20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Question:
56. The stop light switch?

  • Tells you when the air brake system is low on air pressure.
  • Tells you when you need to use your emergency brakes.
  • Turns on the brake lights when you put on the air brakes.
A

Turns on the brake lights when you put on the air brakes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Question:
57. The air compressor stops pumping air at what psi?

  • 125.
  • 100.
  • 150.
A

125

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Question:
58. Repeatedly partially increasing and pressing the brake pedal may result in?

  • A loss of brake air pressure.
  • No change of brake air pressure.
  • A buildup of brake air pressure.
A

A loss of brake air pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Question:
59. To check the free play of manual slack adjusters of S-cam brakes, you should park on?

  • Level ground, chock the wheels and release the parking brakes.
  • Level ground and drain off air pressure before checking the adjustment.
  • Level ground and apply the parking brakes, then apply service brakes.
A

Level ground, chock the wheels and release the parking brakes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Question:
60. The safety valve is set automatically?

  • 100.
  • 50.
  • 150.
A

150.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Question:
61. Your truck or bus has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?

  • Reduce you speed and drive to the nearest garage for repairs.
  • Reduce your speed and test the remaining system while under way.
  • Stop right away and safely park. Continue only after the system is fixed.
A

Stop right away and safely park. Continue only after the system is fixed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Question:
62. The supply pressure gauge shows how much pressure?

  • Is going to the brake chamber.
  • You have used in this trip.
  • Is in the air tanks.
A

Is in the air tanks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Question:
63. Your truck has dual air system, and one of the system loses its pressure. What will happen?

  • The manual slack adjusters of the S-cam brakes will not be set properly.
  • Brake drums will not be fully pressurized.
  • Either the front or back brake will not be fully operational.
A

Either the front or back brake will not be fully operational.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Question:
64. What air brake vehicles, the parking brakes should be used?

  • Any time when vehicle is parked.
  • To hold your speed when going downhill.
  • As little as possible.
A

Any time when vehicle is parked.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Question:
65. The most common type of foundation brake found on heavy vehicles is the?

  • S-cam drum.
  • Disc.
  • Wedge drum.
A

S-cam drum.

66
Q

Question:
66. If your truck has a dual air brake system, and one of the system is low on pressure?

  • Either the front or rear brakes will not be fully functional.
  • The manual slack adjusters on S-cam brakes are not set properly.
  • The brakes drums will not be fully operational.
A

Either the front or rear brakes will not be fully functional.

67
Q

Question:
67. The braking power of the springs brakes?

  • Can only be tested by highly trained brake service people.
  • Depends on the brakes being in adjustment.
  • Is not affected by the condition of the service brakes.
A

Depends on the brakes being in adjustment.

68
Q

Question:
68. The air loss rate for a straight truck or bus with the engine off and the brakes on should not be more than?

  • 3 psi in one minute.
  • 2 psi in 45 seconds.
  • 1 psi in 30 seconds.
A

3 psi in one minute.

69
Q

Question:
69. With air brake vehicles, the parking brake should be used?

  • Only during pre-trip inspection.
  • Whenever you leave the vehicle unattended.
  • As little as possible.
A

Whenever you leave the vehicle unattended.

70
Q

Question:
70. If air pressure is not built up within the correct amount of time, then?

  • Air pressure may drop to a low point while driving, requiring an emergency stop.
  • The alcohol container may be low.
  • You should be ready to use your parking brakes to stop.
A

Air pressure may drop to a low point while driving, requiring an emergency stop.

71
Q

Question:
71. The proper use of the brakes when going down a long steep grade after selecting a proper gear is to brake until your speed is about _________ below the posted speed and release your brake?

  • 10 mph
  • 5 mph
  • 15 mph
72
Q

Question:
72. It is not safe to drive a vehicle that has brake drums with cracks that are longer than ______ of the width of the friction area?

  • 1/2
  • 1/4
  • 1/8
73
Q

Question:
73. Your truck or bus has a dual air brake system. If a low-pressure warning comes on for only on system, what should you do?

  • Bring your vehicle to a complete stop right away and safely park. Continue only after the system is fixed.
  • Reduce your speed and drive to the nearest garage for repairs.
  • Reduce your speed and test the remaining system while under way.
A

Bring your vehicle to a complete stop right away and safely park. Continue only after the system is fixed.

74
Q

Question:
74. Some air brake systems have an alcohol evaporator. What may happen if you don’t keep the proper level of alcohol?

  • The S-cam may not take back when you release the brake pedal.
  • Ice may form on the brake drums and wear them out.
  • Ice may form in the air brake valves and cause brake failure.
A

Ice may form in the air brake valves and cause brake failure.

75
Q

Question:
75. The safety valve reduces pressure at _____ psi?

  • 50.
  • 100.
  • 150.
76
Q

Question:
76. The application pressure gauge shows how much air pressure you?

  • Are applying to the brakes.
  • Have in the air tanks.
  • Have in a modulating control valve.
A

Are applying to the brakes.

77
Q

Question:
77. If the air compressor should develop a leak, what keeps the air in the tanks?

  • The one-way check valve.
  • The tractor protection valve.
  • The emergency relay valve.
A

The one-way check valve.

78
Q

Question:
78. When brakes are applied, the brake shoes will press against the?

  • S-cam.
  • Slack adjuster.
  • Brake drum or disc.
A

Brake drum or disc.

79
Q

Question:
79. If you must make an emergency stop, you should brake so you?

  • Use the full power of the brakes to lock them.
  • Use the hand brake before the brake pedal.
  • Can keep your vehicle in straight line.
A

Can keep your vehicle in straight line.

80
Q

Question:
80. What happens when your brake drums get very hot?

  • They expand.
  • They start to smoke.
  • They contract.
A

They expand.

81
Q

Question:
81. Modern air brakes combine three different system. They are the service, the parking, and the _________ brakes?

  • Drum.
  • Emergency.
  • Foot.
A

Emergency.

82
Q

Question:
82. What can legally hold a parking or emergency brake in position for a truck, truck tractor, or bus?

  • Fluid pressure.
  • Air pressure.
  • Spring pressure.
A

Spring pressure.

83
Q

Question:
83. Air brakes takes more time than hydraulic braking because?

  • Air brakes require heavier return springs.
  • Air brakes take more time to flow through the lines than hydraulic fluid.
  • Air brakes use different brake drums.
A

Air brakes take more time to flow through the lines than hydraulic fluid.

84
Q

Question:
84. Why should drain water from compressed air tanks?

  • Water low boiling point reduces braking power.
  • Water can freeze in cold weather and cause brake failure.
  • To keep from fowling the air compressor oil.
A

Water can freeze in cold weather and cause brake failure.

85
Q

Question:
85. The most important thing to do when a low air pressure warning comes on is?

  • Downshift.
  • Stop and safely park as soon as possible.
  • Up-shift.
A

Stop and safely park as soon as possible.

86
Q

Question:
86. The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away like?

  • Hydraulic pressure.
  • Spring pressure.
  • Air pressure.
A

Spring pressure.

87
Q

Question:
87. IF you do not have automatic tank drains, how often should you drain the oil and water from the bottom of compressed air storage tanks?

  • At the end of each day of driving.
  • After every four hours of service.
  • Once a week.
A

At the endo of each day of driving.

88
Q

Question:
88. If your truck or bus has dual parking control valves, you can use pressure from a separate tank to?

  • Balance the service brake system when you are parked.
  • Stay parked twice as long without using up service air pressure.
  • Release the spring emergency/parking brakes to move a short distance.
A

Release the spring emergency/parking brakes to move a short distance.

89
Q

Question:
89. How should you check that your service brakes are working properly?

  • Park on slight grade, drain off air pressure, set parking brake and check to the movement.
  • Park on level ground, wait until normal pressure is reached, release the parking brake and move forward slowly at about 5 mph. Then apply the brakes firmly.
  • Park on level ground, chock the wheels, engage the parking brakes when you have the correct amount of air pressure to do so and shut the engine off.
A

Park on level ground, wait until normal pressure is reached, release the parking brake and move forward slowly at about 5 mph. Then apply the brakes firmly.

90
Q

Question:
90. Which of these is NOT a proper time to apply the parking brakes?

  • If the brakes are very hot (e.g. Just after coming down a steep grade).
  • If you will be stopping for only one hour.
  • If you are going to test the parking brake to make sure that it holds the vehicle.
A

If the brakes are very hot (e.g. Just after coming down a steep grade).

91
Q

Question:
91. A slack adjuster’s free play needs to be adjusted if it is more than about _________ when you pull hard on it?

  • 1/4 inch.
  • 1/2 inch.
  • 1 inch.
92
Q

Question:
92. Parking or emergency brakes of trucks and buses can be legally held on by ______ pressure?

  • Spring.
  • Air.
  • Fluid.
93
Q

Question:
93. When is it OK to leave your truck unattended without applying the parking brakes and choking the wheels?

  • If you are conducting a pre-trip inspection.
  • If you are only away for a few minutes.
  • Never.
94
Q

Question:
94. Excessive heat caused by using your brakes too often can also cause?

  • Brake to fade or fail.
  • Modulated control valve to wear out.
  • Brake linings to split up.
A

Brake to fade or fail.

95
Q

Question:
95. The air compressor governor controls?

  • Air pressure applied to the brakes.
  • The speed of the air compressor.
  • When air is pumped into the air tanks.
A

When air is pumped into the air tanks.

96
Q

Question:
96. The use of brakes on a long and steep downgrade under normal conditions is only a supplement to?

  • Use of spring brakes.
  • The braking effect of the engine.
  • The use of the front brakes limiting valve.
A

The braking effect of the engine.

97
Q

Question:
97. Your brakes are fading when?

  • Less pressure is needed on the brake pedal for each stop.
  • You have to push harder on a brake pedal to control your speed on a downgrade.
  • The brake pedal feels spongy when you apply pressure.
A

You have to push harder on a brake pedal to control your speed on a downgrade.

98
Q

Question:
98. Why drain water from compressed air tanks?

  • Water cools the compressor too much.
  • Water can freeze in cold weather and cause brake failure.
  • Water low boiling point reduces braking power.
A

Water can freeze in cold weather and cause brake failure.

99
Q

Question:
99. An air brake system is fully charged at what psi?

  • 100.
  • 125.
  • 75.
100
Q

Question:
100. The driver must be able to see a low pressure warning which comes on a before pressure in the service air tanks falls below ______ psi?

  • 80.
  • 60.
  • 40.
101
Q

Question:
102. All air brake-equipped vehicles have?

  • A backup hydraulic system.
  • A supply pressure gauge.
  • An air usage gauge.
A

A supply pressure gauge.

102
Q

Question:
102. Under normal conditions, in order to engage the parking brakes, the driver should?

  • Apply brakes by pulling the parking brake control knob out.
  • Turn off the engine.
  • Be sure air brakes system is fully pressurized.
A

Apply brakes by pulling the parking brake control knob out.

103
Q

Question:
103. The driver musty be able to see a low air pressure warning which comes on before pressure in the service air tanks falls below _____ psi?

  • 60.
  • 80.
  • 50.
104
Q

Question:
104. What is a “Wig Wag”?

  • A spring mount fir hair pieces.
  • A mechanical arm that signals low air pressure.
  • Part of the stop light system.
A

A mechanical arm that signals low air pressure.

105
Q

Question:
105. The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below _______ psi?

  • 60.
  • 20.
  • 100.
106
Q

Question:
106. If your vehicle has an alcohol evaporator, it is there to?

  • Boost tank pressure, the same way that turbocharges boost engine.
  • Reduced the risk of icing in air brake valves in cold weather.
  • Eliminate the need for daily tank draining.
A

Reduced the risk of icing in air brake valves in cold weather.

107
Q

Question:
To test air service brake, you should?

  • Brake firmly while slowly moving forward.
  • Stop the vehicle, brake in a low gear, depress the service brakes, and then gently pull against the brakes.
  • Brake slowly while slowly moving backward.
A

Brake firmly while slowly moving forward.

108
Q

Question:
108. Stab braking?

  • Use light steady pressure on the brake pedal.
  • Press hard on brake pedal and apply the hand valve as you stop.
  • Apply your brakes all the way. Release the brakes when wheels lock up. As soon as the wheels start rolling, apply the brakes fully again.
A

Apply your brakes all the way. Release the brakes when wheels lock up. As soon as the wheels start rolling, apply the brakes fully again.

109
Q

Question:
109. The brakes pedal in an air brake system?

  • Controls the speed of the air compressor.
  • Is connected to slack adjusters by a series of rods and linkages.
  • Controls the air pressure applied to the brakes.
A

Controls the air pressure applied to the brakes.

110
Q

Question:
110. The S-cam?

  • Forces the brake shoes against the inside of the brake drum.
  • Pulls the brake shoes away from the drum and allow the wheels to roll freely.
  • Controls the air flow to each of the brake chambers.
A

Forces the brake shoes against the inside of the brake drum.

111
Q

Question:
The air brake lad distance at 55 mph on dry pavement adds about _______ feet.

  • 52.
  • 32.
  • 12.
112
Q

Question:
112. How should you check the your service brakes are working properly?

  • Park on level ground, wait until normal air pressure is reached, release the parking brake and move forward slowly at about 5 mph. Then apply the brakes firmly.
  • Park on level ground, chock the wheels, engage the parking brakes when you have the correct amount of air pressure to do so and shut the engine off.
  • Park on slight grade, drain off air pressure, set parking brake and check to the movement.
A

Park on level ground, wait until normal air pressure is reached, release the parking brake and move forward slowly at about 5 mph. Then apply the brakes firmly.

113
Q

Question:
113. What keeps an engine cool in hot weather while driving?

  • Air conditioner use.
  • High speed driving in order to put more air to the radiator.
  • Enough engine oil level.
A

Enough engine oil level.

114
Q

Question:
114. Which of these statements about vehicle fire is true?

  • If your engine is on fire, you should open the hood as soon as you can.
  • A burning tire should be cooled with water.
  • If cargo in a van or box trailer catches on fire, you should open the cargo door as soon as possible.
A

A burning tire should be cooled with water.

115
Q

Question:
115. What should you do before driving in the mountains?

  • Unhook your steering axle brake.
  • Know escape ramp locations on your way.
  • Carry the tire chains in your vehicle.
A

Know escape ramp locations on your way.

116
Q

Question:
116. The BAC (Blood Alcohol Concentration) for commercial drivers to be considered intoxicated when driving a commercial vehicle is?

  • 0.10.
  • 0.01.
  • 0.04.
117
Q

Question:
Which of these is true about radiator shutters and the winter front during winter driving?

  • The engine may overheat if winter-front left open.
  • The winter front should be closed tightly.
  • Ice should be removed from the radiator shutter.
A

Ice should be removed from the radiator shutter.

118
Q

Question:
118. Which of these is true about the use of drugs while driving?

  • Prescription or non-prescription drugs allowed if a doctor says they will not affect the driving ability.
  • Us of amphetamine is allowed if you are using this drug to stay alert.
A

Prescription or non-prescription drugs allowed if a doctor says they will not affect the driving ability.

119
Q

Question:
119. Which of these is true about notifying the authorities after an accident?

  • You should notify authorities about an accident before doing anything else.
  • If you have a cellular phone or CD radio you should notify the authorities before exiting the vehicle.
  • An exact location is not necessary just identify the road and the vehicle involved.
A

If you have a cellular phone or CD radio you should notify the authorities before exiting the vehicle.

120
Q

Question:
120. A key principle to remember about loading cargo is to keep the load?

  • To the rear.
  • To the front.
  • Balanced in the cargo area.
A

Balanced in the cargo area.

121
Q

Question:
121. You are driving a vehicle that could be driven safely 55 mph on an open road. But traffic is heavy, and other vehicles drive at the speed of 35 mph, though the speed limits is 55 mph. The safest speed for your vehicle is more likely to be?

  • 35 mph.
  • 55 mph.
  • 45 mph.
122
Q

Question:
122. Which of these lights cannot be checked at the same time?

  • Turn signals, brake lights, and four way flasher.
  • Headlights, brake lights, and clearance lights.
  • Turn signals, tail lights, and clearance lights.
A

Turn signals, brake lights, and four way flasher.

123
Q

Question:
123. If a straight vehicle ( not a trailer or articulation ) goes into a front-wheel skid, it will?

  • Go straight ahead but will turn if you turn the steering wheel.
  • Go straight ahead even if the steering wheels is turned.
  • Slid sideways and spin out.
A

Go straight ahead even if the steering wheels is turned.

124
Q

Question:
124. What is true about bad weather and driving conditions?

  • When the temperature drops, the bridges freeze before the road.
  • The road is more slippery when the rain continues than when rain begins.
  • Driving condition became more dangerous when temperature arises above freezing.
A

When the temperature drops, the bridges freeze before the road.

125
Q

Question:
125. Which of these statements about alcohol is NOT true?

  • BAC is determined by how fast you drink; how much you drink and how much you eat.
  • Alcohol goes directly from the stomach to the blood stream.
  • A drinker can control how fast his or her body absorbs alcohol.
A

A drinker can control how fast his or her body absorbs alcohol.

126
Q

Question:
126. Which of these would NOT help if the windshield is covered with ice?

  • Windshield scraper.
  • Dust brush.
  • Windshield defroster.
A

Dust brush.

127
Q

Question:
127. What should you do if you are unsure whether you have enough overhead clearance?

  • Estimate the height of topped overhead object if it is not posted.
  • Slow down slightly and try to drive under object.
  • Find another route that will not require driving under the object.
A

Find another route that will not require driving under the object.

128
Q

Question:
128. If you need to leave the road in a traffic emergency, you should?

  • Avoid braking until your speed has dropped to about 20 mph.
  • Try to get all wheels off the pavement.
  • Avoid shoulder because most will not support a large vehicle.
A

Avoid braking until your speed has dropped to about 20 mph.

129
Q

Question:
129. When driving at night, you should use your high beams when oncoming traffic is not within ________ feet?

  • 300.
  • 400.
  • 500.
130
Q

Question:
130. If you do not have a CB-radio, what procedure should you follow on an accident scene?

  • Protect the area.
  • Notify the authorities.
  • Care for the injured person.
A

Protect the area.

131
Q

Question:
131. Heavy vehicles often move slower than others. Which of these is NOT a good rule to follow while driving a heavy vehicle?

  • Stay on the right side of the road.
  • Signal other drivers when it is safe to pass you.
  • Use four-way flasher if it is legal in your state.
A

Signal other drivers when it is safe to pass you.

132
Q

Question:
132. Which of the following systems should receive extra attention during winter weather inspection?

  • Exhaust.
  • Suspension.
  • Steering,
133
Q

Question:
133. What is the term for a commercial vehicle habit of swinging wide on turns?

  • Off-Tracking.
  • Wide rounding.
  • Side Winding.
A

Off-Tracking.

134
Q

Question:
134. Brake drums (or discs) must not have cracks longer than ______ the width of the friction area?

  • 1/3.
  • 1/2.
  • 1/10.
135
Q

Question:
135. Sometimes you need to leave a road to avoid a hazard or emergency. When you do, you should keep in mind that?

  • Most shoulder are not strong enough to support a heavy vehicle.
  • It is less dangerous to drive onto the shoulder than to cause a collision.
  • You might be unable to re-enter the road because of the gavel used on shoulders.
A

It is less dangerous to drive onto the shoulder than to cause a collision.

136
Q

Question:
136. Which of the statements about backing a heavy vehicle is NOT true?

  • You should back and turn toward the drivers side whenever it is possible.
  • You should use a helper and communicate with him with hand signals.
  • Because you cannot see, you should back slowly until you slightly bump into the dock.
A

Because you cannot see, you should back slowly until you slightly bump into the dock.

137
Q

Question:
137. You must stop on a hill or curve on a two-lane, two-way road. How far should you place reflective triangles?

  • As far back as necessary so other can see you.
  • Within 200 feet behind you,
  • Within 500 feet behind you.
A

Within 500 feet behind you.

138
Q

Question:
138. During the vehicle inspection, checking of _______ will NOT prevent a fire?

  • Cargo ventilation.
  • Electrical system isolation.
  • Battery fluid level.
A

Battery fluid level.

139
Q

Question:
139. Which of these statements about engine overheating is true?

  • You should never shut off an overheated engine until it cools.
  • Antifreeze is not needed when the weather is warm.
  • You should never remove the radiator cap on a pressurized system until the system is cooled.
A

You should never remove the radiator cap on a pressurized system until the system is cooled.

140
Q

Question:
140. The tread depth on front steering wheel tires should be?

  • Not less than 4/32 inch.
  • More than 6/32 inch.
  • Not less than 2/32 inch,
A

Not less than 4/32 inch.

141
Q

Question:
141. Which of these is NOT something you should do if your headlight are not working properly?

  • Adjust headlights.
  • Clean your headlights.
  • Leave on your high beams.
A

Leave on your high beams.

142
Q

Question:
142. Your are inspecting hydraulic brakes. You should pump the brake pedal three times, then apply firm pressure to the pedal for five seconds. If the brakes are working properly, the pedal should?

  • Depress slightly.
  • Not Move.
  • Sink to the floor.
143
Q

Question:
143. If you are not sure what to use to put out a hazardous material fire, you should?

  • Use dirt,
  • Wait for fire fighters.
  • Use water.
A

Wait for fire fighters.

144
Q

Question:
144. Your vehicle has hydraulic brakes. While traveling on a level road, you press the brake pedal and find that it goes to the floor. Which of these statements is true?

  • The parking brake will not work either because it is part if the same hydraulic system.
  • Pumping the brake pedal may bring the pressure up so you can stop the vehicle.
  • Shifting into neutral will help to slow the vehicle.
A

Pumping the brake pedal may bring the pressure up so you can stop the vehicle.

145
Q

Question:
145. After starting the engine?

  • The engine temperature gauge will take 3-5 minutes to rise to normal.
  • The coolant temperature gauge should begin a gradual rise to normal.
  • The oil pressure gauge should take 3-5 minutes to rise to normal.
A

The coolant temperature gauge should begin a gradual rise to normal.

146
Q

Question:
146. You are driving a 40-foot vehicle at 35 mph. The road is dry, and visibility is good. What is the least amount of space you should keep in front of your vehicle to be safe?

  • 5 seconds.
  • 3 seconds.
  • 4 seconds.
A

4 seconds.

147
Q

Question:
147. You are checking your brakes and suspension system for a pre-trip inspection. Which of these statements is true?

  • Brake shoes should not have oil, grease, or brake fluid on them.
  • Just one missing leaf in a leaf spring is not dangerous.
  • Spring hangers that are cracked but still tight are not dangerous.
A

Brake shoes should not have oil, grease, or brake fluid on them.

148
Q

Question:
148. When driving through the work zone, you should?

  • Watch for sharp pavement drop off.
  • Reduce your speed only if workers are close the roadway.
  • Turn on your parking lights.
A

Watch for sharp pavement drop off.

149
Q

Question:
149. Hydroplaning?

  • Is more likely if tire pressure is low.
  • Cannot occur when driving through a puddle.
  • Only occurs when there is a lot of water.
A

Is more likely if tire pressure is low.

150
Q

Question:
150. You are traveling down a long, steep hill. Your brakes get so hot that they have failed. What should you do?

  • Downshift and pump the brake pedal.
  • Look for an escape ramp or escape route.
  • BOTH
A

Look for an escape ramp or escape route.

151
Q

Question:
151. You may hang up on a railroad track if?

  • You try to shift gear when crossing.
  • The tracks have a sleep approach.
  • If you cross the double tracks too slowly.
A

The tracks have a sleep approach.

152
Q

Question:
152. If you are being tailgated, you should?

  • Flash your brake lights.
  • Increase your following distance.
  • Signal the tailgater when it is safe to pass you.
A

Increase your following distance.

153
Q

Question:
154. You are driving on a two-lane road. An oncoming driver drifts into your lane and is headed straight for you. Which of these is most often the best action to take?

  • Hard braking.
  • Steer onto the left shoulder.
  • Steer to the right.
A

Steer to the right.

154
Q

Question:
155. The best drivers are those who watch and prepare for hazards. This is called _______ driving?

  • Objective.
  • Offensive.
  • Defensive,
A

Defensive.

155
Q

Question:
155. Which of these is NOT a danger when an automatic transmission is forced into a low gear at a high speed?

  • Damage to the transmission.
  • A loss of steering control.
  • A loss of engine braking effect,
A

A loss of steering control.

156
Q

Question:
156. Which of these is the most important thing to remember about emergency braking?

  • Disconnecting the steering axle brakes will keep your vehicle in a straight-line during emergency braking.
  • If the wheels are skidding, you cannot control your vehicle.
  • Never do it without downshifting first.
A

If the wheels are skidding, you cannot control your vehicle.

157
Q

Question:
157. What should you do when you see a hazard in the roadway ahead of you?

  • Stop quickly and pull to the side of the road.
  • Steer around it and get back in your lane.
  • Use your four-way flashers or brake lights to warn others.
A

Use your four-way flashers or brake lights to warn others.

158
Q

Question:
158. Extra care is needed to keep your Vehicle centered in your lane because commercial vehicles?

  • Tend to sway from time to time.
  • Require a lot of room to change lane.
  • Are often wider than other vehicles.
A

Are often wider than other vehicles.

159
Q

Question:
159. How does the weight of the vehicle affect stopping distance?

  • Fully loaded trucks take longer to stop, or the buses loaded with passengers take less distance than empty ones.
  • If brakes work weight will have no effect on stopping distance.
  • Empty trucks take longer to stop than if loaded but this is not the normal case for buses.
A

Empty trucks take longer to stop than if loaded but this is not the normal case for buses.

160
Q

Question:
160. A Hazard?

  • Cannot turn into emergency.
  • Does not need to be seen.
  • Is any road condition or other road user that is possible danger.
A

Is any road condition or other road user that is possible danger.

161
Q

Question:
161. Which of the statements about driving in areas with strong wind is true?

  • The lighter your vehicle, the less trouble you will have with the wind.
  • Winds are especially a problem when coming out of tunnels.
  • You should drive alongside other vehicles to help brake up the wind,
A

Winds are especially a problem when coming out of tunnels.

162
Q

Question:
162. Which of these is a good thing to do when driving at night?

  • Look directly at the oncoming headlights only briefly.
  • Keep your speed slow enough that you can stop within the range of your headlights.
  • Keep your instrument lights bright.
A

Keep your speed slow enough that you can stop within the range of your headlights.

CDL-Class (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions