CDL general knowledge practice test

Who takes this test

Every CDL applicant takes the general knowledge test.

Manual section 1.1.1, Knowledge Tests, page 1-5. Our questions come from Section 2 of the manual.

The CDL manual

Key numbers from the manual

Questions about the general knowledge test

All 100 questions and answers

Read the bank before a mock test. Each answer names the manual section and the printed page.

1. 1.What is the most important reason for doing a vehicle inspection?

   2.1.1 – Why Inspect

   • Safety for yourself and other road users

   The manual says safety is the most important reason you inspect your vehicle, for yourself and for other road users. Manual: 2.1.1 – Why Inspect, page 2-1.

2. 2.You need at least how much tread depth in every major groove on the front tires of a commercial vehicle?

   2.1.3 – What to Look For

   • 4/32 inch

   The manual requires at least 4/32-inch tread depth in every major groove on front tires. Manual: 2.1.3 – What to Look For, page 2-1.

3. 3.You need at least how much tread depth in every major groove on tires other than the front tires?

   2.1.3 – What to Look For

   • 2/32 inch

   The manual requires at least 2/32 inch of tread depth on tires other than the front tires. Manual: 2.1.3 – What to Look For, page 2-1.

4. 4.How much steering wheel play is too much and can make a vehicle hard to steer?

   2.1.3 – What to Look For

   • More than 10 degrees

   Steering wheel play of more than 10 degrees, about 2 inches at the rim of a 20-inch wheel, can make it hard to steer. Manual: 2.1.3 – What to Look For, page 2-2.

5. 5.Which of these is the required emergency equipment for a commercial vehicle?

   2.1.3 – What to Look For

   • A fire extinguisher, spare electrical fuses, and warning devices

   The manual lists a fire extinguisher, spare electrical fuses unless the vehicle has circuit breakers, and warning devices for parked vehicles. Manual: 2.1.3 – What to Look For, page 2-3.

6. 6.During the engine start check, air pressure should build from 50 to 90 psi within what time?

   2.1.5 – Seven-step Inspection Method

   • 3 minutes

   The manual says air pressure should build from 50 to 90 psi within 3 minutes. Manual: 2.1.5 – Seven-step Inspection Method, page 2-4.

7. 7.What should the anti-lock braking system indicator light do if the ABS is working properly?

   2.1.5 – Seven-step Inspection Method

   • Come on briefly at start-up and then go out

   The ABS indicator light should come on when the engine starts and then turn off; if it stays on, the ABS is not working properly. Manual: 2.1.5 – Seven-step Inspection Method, page 2-4.

8. 8.How do you test a hydraulic brake system for leaks during the inspection?

   2.1.5 – Seven-step Inspection Method

   • Pump the pedal three times, then hold firm pressure for five seconds

   The manual says to pump the brake pedal three times, apply firm pressure, hold for five seconds, and the pedal should not move. Manual: 2.1.5 – Seven-step Inspection Method, page 2-7.

9. 9.When transporting cargo, when must you inspect the cargo securement during a trip?

   2.1.6 – Inspection during a Trip

   • Within the first 50 miles, then every 150 miles or every 3 hours

   Drivers transporting cargo must inspect securement within the first 50 miles and every 150 miles or 3 hours, whichever comes first. Manual: 2.1.6 – Inspection during a Trip, page 2-7.

10. 10.What should you do to keep from rolling back when you start on a hill?

    2.2.1 – Accelerating

    • Partly engage the clutch before taking your foot off the brake

    With a manual transmission, partly engage the clutch before taking your right foot off the brake, and use the parking brake whenever necessary. Manual: 2.2.1 – Accelerating, page 2-8.

11. 11.Why should you back and turn toward the driver's side whenever possible?

    2.2.4 – Backing Safely

    • You can see the rear of the vehicle by looking out the side window

    Backing toward the driver's side lets you watch the rear of your vehicle by looking out the side window, while backing to the right is very dangerous. Manual: 2.2.4 – Backing Safely, page 2-9.

12. 12.Where should a helper stand while you back your vehicle?

    2.2.4 – Backing Safely

    • Near the back of the vehicle where you can see the helper

    The helper should stand near the back of the vehicle where you can see the helper, and you should agree on hand signals including one for stop. Manual: 2.2.4 – Backing Safely, page 2-9.

13. 13.Most heavy vehicles with unsynchronized manual transmissions require what shifting method?

    2.3.1 – Manual Transmissions

    • Double clutching

    The manual says unsynchronized manual transmissions require double clutching to change gears. Manual: 2.3.1 – Manual Transmissions, page 2-9.

14. 14.What gear should you be in before you start down a long, steep hill?

    2.3.1 – Manual Transmissions

    • A low enough gear, usually lower than the gear needed to climb the hill

    Shift down before starting down the hill and make sure you are in a low enough gear, usually lower than the gear required to climb the same hill. Manual: 2.3.1 – Manual Transmissions, page 2-9.

15. 15.When should you downshift before entering a curve?

    2.3.1 – Manual Transmissions

    • Before entering the curve, so you can use some power through it

    Slow to a safe speed and downshift to the right gear before entering the curve so you can use some power through the curve. Manual: 2.3.1 – Manual Transmissions, page 2-10.

16. 16.Which wheels does a retarder apply braking power to?

    2.3.4 – Retarders

    • The drive wheels only

    The manual says when turned on, retarders apply their braking power to the drive wheels only. Manual: 2.3.4 – Retarders, page 2-10.

17. 17.When must you turn a retarder off?

    2.3.4 – Retarders

    • Whenever the road is wet, icy, or snow covered

    When the drive wheels have poor traction the retarder may cause them to skid, so turn it off when the road is wet, icy, or snow covered. Manual: 2.3.4 – Retarders, page 2-10.

18. 18.How far ahead should most good drivers look?

    2.4.1 – Seeing Ahead

    • At least 12 to 15 seconds

    Most good drivers look at least 12 to 15 seconds ahead, which is about one block at low speeds and about a quarter mile at highway speeds. Manual: 2.4.1 – Seeing Ahead, page 2-10.

19. 19.When can mirrors be accurately adjusted on a combination vehicle?

    2.4.2 – Seeing to the Sides and Rear

    • Only when the trailer or trailers are straight

    Mirror adjustment should be checked before a trip and can only be checked accurately when the trailer or trailers are straight. Manual: 2.4.2 – Seeing to the Sides and Rear, page 2-11.

20. 20.How do objects appear in a convex mirror compared with looking at them directly?

    2.4.2 – Seeing to the Sides and Rear

    • Smaller and farther away

    Everything appears smaller in a convex mirror and seems farther away than it really is, so you must allow for that. Manual: 2.4.2 – Seeing to the Sides and Rear, page 2-11.

21. 21.Which of these is one of the three good rules for using turn signals?

    2.5.1 – Signal Your Intentions

    • Signal early, signal continuously, and cancel the signal when done

    The three rules are to signal early, keep the signal on until the turn is completed, and cancel it afterward. Manual: 2.5.1 – Signal Your Intentions, page 2-12.

22. 22.How can you warn drivers behind you that you need to slow down?

    2.5.2 – Communicating Your Presence

    • Light taps on the brake pedal to flash the brake lights

    A few light taps on the brake pedal, enough to flash the brake lights, warn following drivers that you are slowing down. Manual: 2.5.2 – Communicating Your Presence, page 2-12.

23. 23.Why should you never signal other drivers that it is safe to pass?

    2.5.2 – Communicating Your Presence

    • You could cause a crash and be blamed for it

    The manual warns that you should not direct traffic; you could cause an accident, be blamed, and it could cost you thousands of dollars. Manual: 2.5.2 – Communicating Your Presence, page 2-12.

24. 24.On a divided highway, where should you place warning devices if you must stop?

    2.5.2 – Communicating Your Presence

    • 10 feet, 100 feet, and 200 feet toward the approaching traffic

    On a one-way or divided highway, place warning devices 10 feet, 100 feet, and 200 feet toward the approaching traffic. Manual: 2.5.2 – Communicating Your Presence, page 2-12.

25. 25.If your stopped vehicle is hidden by a hill or curve, where should the rearmost warning device go?

    2.5.2 – Communicating Your Presence

    • Back down the road up to 500 feet so drivers get warning in time

    If a hill, curve, or other obstruction prevents drivers from seeing the vehicle within 500 feet, move the rearmost triangle back down the road. Manual: 2.5.2 – Communicating Your Presence, page 2-13.

26. 26.Which three distances add up to total stopping distance?

    2.6.1 – Stopping Distance

    • Perception distance, reaction distance, and braking distance

    Perception distance plus reaction distance plus braking distance equals total stopping distance. Manual: 2.6.1 – Stopping Distance, page 2-14.

27. 27.What is the average perception time for an alert driver?

    2.6.1 – Stopping Distance

    • 1 3/4 seconds

    The average perception time for an alert driver is 1 3/4 seconds, which accounts for 142 feet traveled at 55 mph. Manual: 2.6.1 – Stopping Distance, page 2-14.

28. 28.At 55 mph on dry pavement with good brakes, about how far does the vehicle travel while braking?

    2.6.1 – Stopping Distance

    • 216 feet

    At 55 mph on dry pavement with good brakes, braking distance is about 216 feet. Manual: 2.6.1 – Stopping Distance, page 2-14.

29. 29.At 55 mph, the total minimum stopping distance is at least how far?

    2.6.1 – Stopping Distance

    • 419 feet

    At 55 mph the total stopping distance is a minimum of 419 feet, including perception, reaction, and braking distance. Manual: 2.6.1 – Stopping Distance, page 2-14.

30. 30.How does an empty truck compare with a loaded truck in stopping distance?

    2.6.1 – Stopping Distance

    • An empty truck requires a greater stopping distance

    Empty trucks require greater stopping distances because an empty vehicle has less traction. Manual: 2.6.1 – Stopping Distance, page 2-15.

31. 31.On a wet road, how much should you reduce your speed?

    2.6.2 – Matching Speed to the Road Surface

    • By about one-third, for example from 55 to about 35 mph

    The manual says to reduce speed by about one-third on a wet road, for example slow from 55 to about 35 mph. Manual: 2.6.2 – Matching Speed to the Road Surface, page 2-15.

32. 32.Hydroplaning can occur at speeds as low as 30 mph when which condition is present?

    2.6.2 – Matching Speed to the Road Surface

    • There is a lot of water on the road and the tires are low or worn

    Hydroplaning can occur as low as 30 mph if there is a lot of water, and it is more likely when tire pressure is low or tread is worn. Manual: 2.6.2 – Matching Speed to the Road Surface, page 2-15.

33. 33.What is black ice?

    2.6.2 – Matching Speed to the Road Surface

    • A thin, clear layer of ice that makes the road look wet

    Black ice is a thin layer clear enough to see the road underneath it, and it makes the road look wet. Manual: 2.6.2 – Matching Speed to the Road Surface, page 2-15.

34. 34.Why is braking in a curve dangerous?

    2.6.3 – Speed and Curves

    • It is easier to lock the wheels and cause a skid

    Braking in a curve is dangerous because it is easier to lock the wheels and cause a skid, so slow down before the curve. Manual: 2.6.3 – Speed and Curves, page 2-15.

35. 35.What is the number one cause of injury and death in roadway work zones?

    2.6.7 – Roadway Work Zones

    • Speeding traffic

    The manual states that speeding traffic is the number one cause of injury and death in roadway work zones. Manual: 2.6.7 – Roadway Work Zones, page 2-16.

36. 36.At speeds below 40 mph, how much following distance should you keep?

    2.7.1 – Space Ahead

    • At least one second for each 10 feet of vehicle length

    Below 40 mph you need at least one second for each 10 feet of vehicle length, and you must add one more second above 40 mph. Manual: 2.7.1 – Space Ahead, page 2-16.

37. 37.At 55 mph, how many seconds of following distance should a 40-foot vehicle leave?

    2.7.1 – Space Ahead

    • 5 seconds

    Over 40 mph you add one second, so a 40-foot vehicle needs 5 seconds and a 60-foot rig needs 7 seconds. Manual: 2.7.1 – Space Ahead, page 2-17.

38. 38.What should you do if you find yourself being tailgated?

    2.7.2 – Space Behind

    • Increase your following distance, avoid quick changes, and do not speed up

    To reduce the chance of a crash when tailgated, avoid quick changes, increase your following distance, do not speed up, and avoid tricks. Manual: 2.7.2 – Space Behind, page 2-17.

39. 39.Why can an empty cargo van be more likely to hit an overhead object than a loaded one?

    2.7.4 – Space Overhead

    • An empty van is higher than a loaded one

    The weight of cargo changes a van's height; an empty van is higher than a loaded one, so getting under a bridge loaded does not mean you can do it empty. Manual: 2.7.4 – Space Overhead, page 2-18.

40. 40.Which of these can cause the ends of a vehicle to drag or hang up?

    2.7.5 – Space Below

    • Drainage channels across roads and railroad tracks

    Drainage channels across roads can cause the ends of some vehicles to drag, and railroad tracks can hang up vehicles with low underneath clearance. Manual: 2.7.5 – Space Below, page 2-18.

41. 41.When making a right turn that requires swinging wide, when should you swing wide?

    2.7.6 – Space for Turns

    • As you complete the turn, keeping the rear close to the curb

    If you cannot make the right turn without entering another lane, turn wide as you complete the turn and keep the rear of the vehicle close to the curb. Manual: 2.7.6 – Space for Turns, page 2-18.

42. 42.When should you start a left turn in a large vehicle?

    2.7.6 – Space for Turns

    • After you have reached the center of the intersection

    On a left turn, make sure you have reached the center of the intersection before you start the turn, or off-tracking may make the left side hit another vehicle. Manual: 2.7.6 – Space for Turns, page 2-18.

43. 43.If there are two left-turn lanes, which one should a large vehicle use?

    2.7.6 – Space for Turns

    • The right turn lane, so the vehicle can be seen more readily

    If there are two turning lanes, always take the right turn lane, because drivers on your left can be more readily seen. Manual: 2.7.6 – Space for Turns, page 2-18.

44. 44.When crossing or entering traffic, why does a large vehicle need a bigger gap than a car?

    2.7.7 – Space Needed to Cross or Enter Traffic

    • Because of slow acceleration and the space large vehicles require

    Slow acceleration and the space large vehicles require mean you may need a much larger gap to enter traffic than you would in a car. Manual: 2.7.7 – Space Needed to Cross or Enter Traffic, page 2-19.

45. 45.What is a hazard, as the manual defines it?

    2.8.1 – Importance of Seeing Hazards

    • Any road condition or other road user that is a possible danger

    A hazard is any road condition or other road user, such as a driver, bicyclist, or pedestrian, that is a possible danger. Manual: 2.8.1 – Importance of Seeing Hazards, page 2-19.

46. 46.What do move-over laws require you to do near a stopped emergency vehicle or work zone?

    2.8.2 – Hazardous Roads

    • Slow down and change lanes if it is safe

    Move-over laws require drivers to slow and change lanes when approaching a roadside incident or emergency vehicle if safety and traffic conditions permit. Manual: 2.8.2 – Hazardous Roads, page 2-19.

47. 47.Which of these is a clue that a driver may be impaired?

    2.8.3 – Drivers Who Are Hazards

    • Weaving across the road or drifting from one side to another

    Weaving, leaving the road, stopping at the wrong time, and speeding up or slowing down suddenly are clues that a driver may be impaired. Manual: 2.8.3 – Drivers Who Are Hazards, page 2-21.

48. 48.What is a mental distraction while driving?

    2.9.3 – Types of Distractions

    • An activity that takes your mind away from the road

    A mental distraction takes your mind away from the road, such as a conversation with a passenger or thinking about something that happened during the day. Manual: 2.9.3 – Types of Distractions, page 2-22.

49. 49.Your CDL is disqualified for how long for a second conviction of using a hand-held mobile phone while operating a CMV within three years?

    2.9.4 – Cell/Mobile Phones

    • 60 days

    A second hand-held phone conviction within three years disqualifies your CDL for 60 days, and three or more offenses bring 120 days. Manual: 2.9.4 – Cell/Mobile Phones, page 2-22.

50. 50.When may you use a hand-held mobile phone while operating a CMV?

    2.9.4 – Cell/Mobile Phones

    • In an emergency, to communicate with law enforcement or emergency services

    The rule has an emergency exception that allows hand-held phone use to communicate with law enforcement officials or other emergency services. Manual: 2.9.4 – Cell/Mobile Phones, page 2-22.

51. 51.How much greater are the odds of a safety-critical event for a CMV driver who texts while driving?

    2.9.5 – Texting

    • 23.2 times greater

    The odds of a safety-critical event are 23.2 times greater for CMV drivers who engage in texting while driving. Manual: 2.9.5 – Texting, page 2-23.

52. 52.What is the difference between aggressive driving and road rage?

    2.10.1 – What Is It?

    • Aggressive driving is selfish and pushy, while road rage is operating with intent to harm others

    Aggressive driving is operating in a selfish, bold, or pushy manner without regard for others, while road rage is operating with intent to harm or assault. Manual: 2.10.1 – What Is It?, page 2-24.

53. 53.What should you do when confronted by an aggressive driver?

    2.10.3 – What You Should Do When Confronted

    • Make every attempt to get out of their way

    The first and most important step when confronted by an aggressive driver is to make every attempt to get out of their way. Manual: 2.10.3 – What You Should Do When Confronted, page 2-24.

54. 54.About how far ahead can you see with low beams and with high beams at night?

    2.11.4 – Vehicle Factors

    • About 250 feet with low beams and 350 to 500 feet with high beams

    With low beams you can see ahead about 250 feet and with high beams about 350 to 500 feet, so you must adjust your speed to your sight distance. Manual: 2.11.4 – Vehicle Factors, page 2-27.

55. 55.How close must an oncoming vehicle or a vehicle you are following be before you dim your headlights?

    2.11.5 – Night Driving Procedures

    • Within 500 feet

    Dim your lights within 500 feet of an oncoming vehicle and when following another vehicle within 500 feet. Manual: 2.11.5 – Night Driving Procedures, page 2-27.

56. 56.How does getting 6 hours of sleep or less affect your crash risk?

    2.11.2 – Driver Factors

    • It triples your risk

    The manual lists sleeping 6 hours or less as a fatigue risk that triples your risk of a crash. Manual: 2.11.2 – Driver Factors, page 2-26.

57. 57.What is the best advice for driving in fog?

    2.12 – Driving in Fog

    • Do not drive; pull off the road into a rest area or truck stop

    The best advice for driving in fog is do not; it is preferable to pull off the road into a rest area or truck stop until visibility is better. Manual: 2.12 – Driving in Fog, page 2-28.

58. 58.Which lights should you use if you must drive in fog?

    2.12 – Driving in Fog

    • Low-beam headlights and fog lights, with four-way flashers on

    In fog you should use low-beam headlights and fog lights for best visibility, turn on your four-way flashers, and avoid passing. Manual: 2.12 – Driving in Fog, page 2-28.

59. 59.What does a lack of spray from other vehicles tell you in winter?

    2.13.2 – Driving

    • Ice has formed on the road

    A lack of spray from other vehicles indicates that ice has formed on the road. Manual: 2.13.2 – Driving, page 2-29.

60. 60.What should you do if your brakes get wet after driving through deep water?

    2.13.2 – Driving

    • Slow down, use a low gear, and apply light pressure to heat and dry them

    After crossing water, slow down, place the transmission in a low gear, maintain light pressure on the brakes to heat and dry them, then make a test stop. Manual: 2.13.2 – Driving, page 2-29.

61. 61.How often should you inspect your tires when driving in very hot weather?

    2.14.1 – Vehicle Checks

    • Every 2 hours or every 100 miles

    Check the tire mounting and air pressure, and inspect the tires every 2 hours or every 100 miles when driving in very hot weather. Manual: 2.14.1 – Vehicle Checks, page 2-29.

62. 62.What should you do if a tire is too hot to touch in very hot weather?

    2.14.1 – Vehicle Checks

    • Remain stopped until the tire cools off

    If a tire is too hot to touch, remain stopped until the tire cools off, or it may blow out or catch fire, and do not let air out of hot tires. Manual: 2.14.1 – Vehicle Checks, page 2-30.

63. 63.Which vehicles are required to stop at railroad-highway crossings?

    2.15.2 – Warning Signs and Devices

    • Passenger and hazardous materials carrying vehicles

    The manual states that all passenger and hazmat carrying vehicles are required to stop at railroad-highway crossings. Manual: 2.15.2 – Warning Signs and Devices, page 2-31.

64. 64.If there is no white stop line painted on the pavement, how close may a vehicle required to stop get to the nearest rail?

    2.15.2 – Warning Signs and Devices

    • No closer than 15 feet or more than 50 feet

    Vehicles required to stop must stop no closer than 15 feet or more than 50 feet from the nearest rail of the nearest track. Manual: 2.15.2 – Warning Signs and Devices, page 2-31.

65. 65.What must you do when a railroad crossing's lights begin to flash?

    2.15.2 – Warning Signs and Devices

    • Stop, because a train is approaching

    When the flashing red lights begin, stop; a train is approaching and you must yield the right-of-way. Manual: 2.15.2 – Warning Signs and Devices, page 2-31.

66. 66.Why must you double check before crossing double railroad tracks?

    2.15.3 – Driving Procedures

    • A train on one track may hide a train on the other track

    A train on one track may hide a train on the other, so look both ways and be sure no other trains are near before starting across. Manual: 2.15.3 – Driving Procedures, page 2-32.

67. 67.How long does it take a typical tractor-trailer to clear a single track and a double track?

    2.15.5 – Crossing the Tracks

    • At least 14 seconds for a single track and more than 15 seconds for a double track

    It takes a typical tractor-trailer at least 14 seconds to clear a single track and more than 15 seconds to clear a double track. Manual: 2.15.5 – Crossing the Tracks, page 2-32.

68. 68.Which of these determines your safe speed on a long, steep downgrade?

    2.16.1 – Select a Safe Speed

    • Total weight of the vehicle and cargo, the grade, road conditions, and weather

    Select a speed that is not too fast for the total weight, length and steepness of the grade, road conditions, and weather. Manual: 2.16.1 – Select a Safe Speed, page 2-32.

69. 69.Why should you not try to downshift after your speed has built up on a downgrade?

    2.16.2 – Select the Right Gear before Starting Down the Grade

    • You may not be able to get back into gear and all engine braking will be lost

    If you try to downshift after your speed has built up, you may not be able to shift into a lower gear or get back into any gear, and all engine braking effect will be lost. Manual: 2.16.2 – Select the Right Gear before Starting Down the Grade, page 2-33.

70. 70.What causes brake fade?

    2.16.3 – Brake Fading or Failure

    • Excessive heat from using the brakes too much instead of engine braking

    Brakes can fade or fail from excessive heat caused by using them too much and not relying on the engine braking effect, and adjustment also affects fade. Manual: 2.16.3 – Brake Fading or Failure, page 2-33.

71. 71.On a long downgrade, when should you release the brakes after applying them?

    2.16.4 – Proper Braking Technique

    • When your speed has been reduced to about five mph below your safe speed

    Apply the brakes just hard enough to feel a definite slowdown, release when you are about five mph below your safe speed, and repeat when speed returns. Manual: 2.16.4 – Proper Braking Technique, page 2-33.

72. 72.What are escape ramps designed to do?

    2.16.4 – Proper Braking Technique

    • Stop runaway vehicles safely using a long bed of loose, soft material

    Escape ramps are made to stop runaway vehicles safely using a long bed of loose, soft material, sometimes combined with an upgrade. Manual: 2.16.4 – Proper Braking Technique, page 2-33.

73. 73.Why should you keep both hands on the steering wheel at all times?

    2.17.1 – Steering to Avoid a Crash

    • So you can turn quickly in an emergency

    To turn quickly in an emergency you must have a firm grip on the steering wheel with both hands, and the best way is to keep them there all the time. Manual: 2.17.1 – Steering to Avoid a Crash, page 2-34.

74. 74.If an oncoming driver has drifted into your lane, which way should you steer?

    2.17.1 – Steering to Avoid a Crash

    • To the right

    If an oncoming driver has drifted into your lane, a move to your right is best, because that driver will naturally return to his or her own lane. Manual: 2.17.1 – Steering to Avoid a Crash, page 2-34.

75. 75.If you have to leave the road in an emergency, what should you do about braking?

    2.17.1 – Steering to Avoid a Crash

    • Avoid using the brakes until your speed drops to about 20 mph

    If you leave the road, avoid braking until your speed has dropped to about 20 mph, then brake gently to avoid skidding on a loose surface. Manual: 2.17.1 – Steering to Avoid a Crash, page 2-34.

76. 76.What is controlled braking?

    2.17.2 – How to Stop Quickly and Safely

    • Applying the brakes as hard as you can without locking the wheels

    With controlled braking you apply the brakes as hard as you can without locking the wheels, keeping steering wheel movements very small. Manual: 2.17.2 – How to Stop Quickly and Safely, page 2-34.

77. 77.What is stab braking?

    2.17.2 – How to Stop Quickly and Safely

    • Applying the brakes fully, releasing when the wheels lock, and reapplying when they roll

    With stab braking you apply the brakes all the way, release when the wheels lock up, and apply fully again as soon as the wheels start rolling. Manual: 2.17.2 – How to Stop Quickly and Safely, page 2-35.

78. 78.If hydraulic brakes fail because of a loss of pressure, what should you do?

    2.17.3 – Brake Failure

    • Downshift, pump the brakes, use the parking brake, and find an escape route

    When hydraulic pressure is lost, downshift, pump the brake pedal to try to build pressure, use the parking brake carefully, and find an escape route. Manual: 2.17.3 – Brake Failure, page 2-35.

79. 79.What should you do immediately if a tire fails while you are driving?

    2.17.4 – Tire Failure

    • Hold the steering wheel firmly and stay off the brake until the vehicle slows

    When a tire fails, hold the steering wheel firmly and stay off the brake; braking could cause loss of control until the vehicle has slowed down. Manual: 2.17.4 – Tire Failure, page 2-35.

80. 80.How does ABS help you?

    2.18.1 – How Antilock Braking Systems Work

    • It keeps the wheels from locking up during hard braking

    ABS keeps your wheels from locking up during hard brake applications and helps you keep the vehicle under control, though it does not necessarily shorten stopping distance. Manual: 2.18.1 – How Antilock Braking Systems Work, page 2-36.

81. 81.Which trucks are required by the Department of Transportation to have ABS?

    2.18.2 – Vehicles Required to Have Antilock Braking Systems

    • Truck tractors with air brakes built on or after March 1, 1997

    ABS is required on truck tractors with air brakes built on or after March 1, 1997, and other air brake vehicles built on or after March 1, 1998. Manual: 2.18.2 – Vehicles Required to Have Antilock Braking Systems, page 2-36.

82. 82.Where are the yellow ABS malfunction lamps on a trailer?

    2.18.3 – How to Know If Your Vehicle Is Equipped with ABS

    • On the left side, either the front or rear corner

    Trailers have yellow ABS malfunction lamps on the left side, either on the front or rear corner, while tractors, trucks, and buses have them on the instrument panel. Manual: 2.18.3 – How to Know If Your Vehicle Is Equipped with ABS, page 2-36.

83. 83.When can you fully apply the brakes in an emergency if you have ABS?

    2.18.6 – Braking with ABS

    • When you have working ABS on all axles

    The one exception to braking normally with ABS is that if you have working ABS on all axles, in an emergency stop you can fully apply the brakes. Manual: 2.18.6 – Braking with ABS, page 2-37.

84. 84.Which of these causes a skid?

    2.19 – Skid Control and Recovery

    • Over-braking, over-steering, over-acceleration, or driving too fast

    A skid happens when tires lose their grip from over-braking, over-steering, over-acceleration, or driving too fast for conditions. Manual: 2.19 – Skid Control and Recovery, page 2-37.

85. 85.How do you correct a drive-wheel braking skid?

    2.19.2 – Correcting a Drive-wheel Braking Skid

    • Stop braking and counter-steer

    To correct a drive-wheel braking skid, stop braking so the rear wheels roll again, counter-steer, and push in the clutch on a very slippery surface. Manual: 2.19.2 – Correcting a Drive-wheel Braking Skid, page 2-37.

86. 86.What is the only way to stop a front-wheel skid?

    2.19.3 – Front-wheel Skids

    • Let the vehicle slow down by stopping turning and braking so hard

    In a front-wheel skid the front end goes straight no matter how much you turn, so the only way to stop the skid is to let the vehicle slow down. Manual: 2.19.3 – Front-wheel Skids, page 2-38.

87. 87.What is the first thing to do at an accident scene?

    2.20.1 – Protect the Area

    • Keep another accident from happening in the same spot

    The first thing to do at an accident scene is to protect the area so another accident does not happen in the same spot. Manual: 2.20.1 – Protect the Area, page 2-38.

88. 88.When should you move a severely injured person?

    2.20.3 – Care for the Injured

    • Only when the danger of fire or passing traffic makes it necessary

    Do not move a severely injured person unless the danger of fire or passing traffic makes it necessary. Manual: 2.20.3 – Care for the Injured, page 2-38.

89. 89.How should you stop heavy bleeding at an accident scene?

    2.20.3 – Care for the Injured

    • Apply direct pressure to the wound

    The manual says to stop heavy bleeding by applying direct pressure to the wound. Manual: 2.20.3 – Care for the Injured, page 2-39.

90. 90.What should you do about the hood if the engine is on fire?

    2.21.3 – Fire Fighting

    • Do not open the hood if you can avoid it; shoot foam through louvers or the radiator

    With an engine fire, turn off the engine as soon as you can and do not open the hood if you can avoid it; shoot foam through louvers, the radiator, or the underside. Manual: 2.21.3 – Fire Fighting, page 2-39.

91. 91.What should you do with the doors of a van or box trailer that is on fire?

    2.21.3 – Fire Fighting

    • Keep the doors shut, especially if the cargo contains hazardous materials

    For a cargo fire in a van or box trailer, keep the doors shut because opening them supplies the fire with oxygen and can make it burn very fast. Manual: 2.21.3 – Fire Fighting, page 2-39.

92. 92.Which fire extinguisher is designed for electrical fires and burning liquids?

    2.21.2 – Fire Prevention

    • B:C type

    The B:C type extinguisher is designed for electrical fires and burning liquids, while A:B:C also works on wood, paper, and cloth. Manual: 2.21.2 – Fire Prevention, page 2-39.

93. 93.How fast can the liver process alcohol?

    2.22.1 – Alcohol and Driving

    • About one-third of an ounce per hour, roughly one drink per hour

    The liver can only process about one-third of an ounce of alcohol per hour, which is less than a standard drink, and this rate is fixed. Manual: 2.22.1 – Alcohol and Driving, page 2-40.

94. 94.Which factors determine your blood alcohol concentration?

    2.22.1 – Alcohol and Driving

    • The amount of alcohol you drink, how fast you drink it, and your weight

    BAC is determined by the amount of alcohol you drink, how fast you drink, and your weight. Manual: 2.22.1 – Alcohol and Driving, page 2-40.

95. 95.Which part of the brain does alcohol affect first?

    2.22.1 – Alcohol and Driving

    • The part that controls judgment and self-control

    Alcohol first affects the part of the brain that controls judgment and self-control, which keeps drinkers from knowing they are getting drunk. Manual: 2.22.1 – Alcohol and Driving, page 2-41.

96. 96.According to the manual's effects table, at what blood alcohol content is a person typically unable to drive?

    2.22.1 – Alcohol and Driving

    • 0.15

    The table lists .15 as the level where a person has impaired balance and movement and is unable to drive, while .08 is the drunk driving limit. Manual: 2.22.1 – Alcohol and Driving, page 2-42.

97. 97.What is the intent of the hazardous materials rules?

    2.23.2 – Why Are There Rules?

    • To contain the product, communicate the risk, and ensure safe drivers and equipment

    The rules intend to contain the product, communicate the risk, and ensure safe drivers and equipment. Manual: 2.23.2 – Why Are There Rules?, page 2-42.

98. 98.How many identical placards must a placarded vehicle have at a minimum?

    2.23.3 – Lists of Regulated Products

    • At least four, on the front, rear, and both sides

    A placarded vehicle must have at least four identical placards, put on the front, rear, and both sides, readable from all four directions. Manual: 2.23.3 – Lists of Regulated Products, page 2-43.

99. 99.Where should a driver keep shipping papers for hazardous materials?

    2.23.3 – Lists of Regulated Products

    • On top of other shipping papers, in a pouch on the driver's door or within reach

    Keep hazardous materials shipping papers on top of other shipping papers and in a pouch on the driver's door, in clear view within reach, or on the driver's seat when out. Manual: 2.23.3 – Lists of Regulated Products, page 2-43.

100. 100.When must your license have a hazardous materials endorsement?

     2.23.3 – Lists of Regulated Products

     • When the vehicle requires placards

     You can drive a vehicle carrying hazardous materials if it does not require placards, but if it does require placards you must have the hazardous materials endorsement. Manual: 2.23.3 – Lists of Regulated Products, page 2-43.

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