DMV Practice LabChange state
WAWashington
DMV Practice LabAll tests

Washington CDL practice questions

Selected knowledge practice, not a complete licensing course or practical training.

Washington CDL Full practice questions

Practice mode
Question 1 of 80
  1. 1. You inspect a different tractor this morning. What approach makes an omitted safety item less likely?
  2. 2. During a truck walk-around, rusty streaks lead away from several wheel nuts. What do they suggest?
  3. 3. A damaged exhaust connection is allowing fumes near your truck cab. Why does it need attention before the trip?
  4. 4. Your trip paperwork and a heavy tool are lying loose beside the pedals. What should you do before moving?
  5. 5. During the guide's stationary hydraulic-brake check, the pedal continues to sink under firm pressure. What is the appropriate response?
  6. 6. For a truck subject to 49 CFR 393.75, which pair gives the minimum major-groove tread depths for front tires and other tires?
  7. 7. A truck tire has adequate tread depth but its tread is separating from the casing. Can it be used for the planned highway trip?
  8. 8. Your truck's safety belt latches, but the webbing is badly frayed. Which conclusion is correct?
  9. 9. Your drive tires begin spinning as you accelerate a heavy truck on a slick surface. How should you respond?
  10. 10. Two safe approaches to a loading area are available. Why is backing toward the driver's side generally preferred?
  11. 11. Before reversing under a loading canopy, you cannot judge its clearance from the cab. What should you do?
  12. 12. A helper is about to guide your truck into a bay. What must the two of you agree on before backing?
  13. 13. Which transmission generally calls for double-clutching to shift gears in the guide's manual-transmission procedure?
  14. 14. You are approaching a long downgrade in a loaded truck. When should you select the appropriate low gear?
  15. 15. You switch to a truck with a different engine and gearbox. How should you decide the proper upshift range?
  16. 16. The road becomes icy while your truck's speed retarder is engaged. What does the CDL guide advise?
  17. 17. For routine road scanning, how far ahead does the CDL guide recommend looking while also checking nearer conditions?
  18. 18. A vehicle looks small and distant in your truck's convex mirror. What should you remember before moving sideways?
  19. 19. You checked the mirrors and then signaled a lane change, but have not moved yet. Why check again?
  20. 20. You complete a right turn in a truck whose indicator does not cancel automatically. What should you do next?
  21. 21. A car driver behind your truck asks you to wave them past. What is the safer response?
  22. 22. Your interstate CMV breaks down on a rural highway shoulder where warning devices are required. When should you place them?
  23. 23. On a straight, level rural divided-highway shoulder, how should you arrange the three required triangles behind a disabled CMV?
  24. 24. When estimating total stopping space, why is the distance traveled before touching the brake important?
  25. 25. Under comparable ideal conditions, doubling speed has roughly what effect on braking distance alone?
  26. 26. Your tall loaded truck approaches a signed curve. Does the posted curve speed guarantee that your truck will not roll over?
  27. 27. On an unlit highway, your stopping distance would extend beyond the area your low beams reveal. What adjustment is needed?
  28. 28. After a dry spell, light rain has just begun on the highway. Why can the surface be particularly slick?
  29. 29. Near freezing, the pavement looks wet but the surface may actually be a thin transparent frozen layer. What is this hazard?
  30. 30. What happens when a truck hydroplanes in standing water?
  31. 31. In good conditions at 35 mph, what starting gap follows the guide's one-second-per-10-feet rule for a 40-foot truck?
  32. 32. For a 60-foot combination at 55 mph in good conditions, what baseline gap follows the guide's length-and-speed rule?
  33. 33. A car is following your truck too closely. Which change helps you avoid a sudden stop that it may not handle?
  34. 34. A van trailer cleared a low structure while loaded. After unloading, is that earlier clearance enough proof for the return trip?
  35. 35. Your low trailer approaches a sharply raised railroad crossing. What must you consider before entering?
  36. 36. Why is swinging left before starting a wide right turn hazardous in a large truck?
  37. 37. You must cross a road with a heavily loaded truck. Compared with a car, what should you plan for?
  38. 38. A cardboard box lies in your truck's lane. What is the prudent assumption while planning a safe response?
  39. 39. A car entering an exit lane suddenly brakes and hesitates. What possible action should you prepare for?
  40. 40. You need directions for a new delivery location. When is the best time to enter the route into your navigation system?
  41. 41. An angry driver repeatedly gestures and tries to get ahead of your truck. What is the safest response?
  42. 42. You have heavy eyelids and cannot remember the last few miles of your truck route. What should you do?
  43. 43. While seeking a safe place to stop in fog, which headlights should you use?
  44. 44. In dense fog, why should you not simply follow a pair of taillights as your guide to the roadway?
  45. 45. Before climbing into a truck after freezing rain, what should you clear as well as the windows?
  46. 46. After highway driving in hot weather, tire pressure is higher than its correct cold setting. What should you avoid?
  47. 47. The engine coolant is very hot. What is the safe approach to a radiator cap that is part of the pressurized system?
  48. 48. After water enters brake drums, how can braking performance change?
  49. 49. One train has cleared a crossing with two tracks. What hazard remains before your truck proceeds?
  50. 50. You have a clear path across the railroad tracks in a manual-transmission truck. How should you handle the gear selection?
  51. 51. On a long descent, repeated heavy service-brake use produces less slowing despite more pedal pressure. What may be happening?
  52. 52. On a dry downgrade, the truck is in the proper low gear and 35 mph is your selected safe speed. Under the guide's braking technique, when do you release an application begun at 35 mph?
  53. 53. Your truck's brakes fail on a descent and a marked escape ramp is available. What should you do?
  54. 54. A front tire suddenly blows out and no collision is immediately unavoidable. What is the guide's first control advice?
  55. 55. You must make an emergency stop in a straight truck with functioning ABS on every axle. Which action does the guide permit?
  56. 56. Which benefit should you expect from functioning ABS during hard braking?
  57. 57. A loaded truck has ABS. Does that make taking a curve too fast safe?
  58. 58. The ABS malfunction lamp comes on while driving, but there is no indication that the regular brakes have failed. What does that lamp mean?
  59. 59. After stopping safely, you suspect a fire under the truck's hood. Should you open it to inspect the flames?
  60. 60. Everyone has escaped a burning truck. Where should you gather while calling 911?
  61. 61. Warehouse staff load and secure your truck while you complete paperwork. Does that remove your responsibility for the load?
  62. 62. A firmly tied load blocks your access to the truck's emergency equipment. Is its arrangement acceptable?
  63. 63. You start a trip with accessible cargo in an interstate truck; no inspection exception applies. When must you first recheck its securement on the road?
  64. 64. With accessible cargo and no exception, you have driven 3 hours but only 110 miles since the last cargo recheck. What is required?
  65. 65. You change duty status after a short drive with an inspectable load. Neither 3 hours nor 150 miles has elapsed. Does the cargo rule still require a recheck?
  66. 66. Your trailer is sealed and you have been ordered not to open it for inspection. What remains important despite that inspection exception?
  67. 67. A loaded truck is within its overall weight limit, but cargo is concentrated over one axle. What must be checked?
  68. 68. When arranging heavy and light freight, which layout generally lowers rollover risk?
  69. 69. Too much cargo weight is shifted toward the back, leaving the front axle too lightly loaded. What can result?
  70. 70. Your truck has too little weight on its drive axles for the conditions. Which difficulty is more likely?
  71. 71. You secure shaped blocks snugly against a crate and fasten them to the deck. What is their main purpose?
  72. 72. Under the general article-securement rule, what minimum aggregate working load limit is needed for an 8,000-pound article?
  73. 73. Under the general tiedown-count rule, an unblocked 4-foot, 900-pound article needs at least how many tiedowns? Assume adequate strength and no special commodity rule.
  74. 74. An 8-foot article weighs only 500 pounds and is not blocked against forward movement. Under the general rule, what is the minimum tiedown count?
  75. 75. A 12-foot article is not blocked against forward movement. Under the general tiedown-count rule, how many are needed at minimum?
  76. 76. A 12-foot article is properly blocked against forward movement. Under the general rule, what is its minimum tiedown count, assuming no special rule applies?
  77. 77. Your tiedowns meet the minimum count, but their calculated aggregate WLL is below the required amount. Is the cargo ready to travel?
  78. 78. Why must a truck's front-end header board be sound and properly secured?
  79. 79. A tarp covers freight on a flatbed. What still needs to be established before driving?
  80. 80. Why does a refrigerated trailer carrying hanging meat call for particular caution on a curved exit ramp?
Review all 80 questions with answers

  1. You inspect a different tractor this morning. What approach makes an omitted safety item less likely?

    Correct answer: Follow the same systematic inspection sequence each time

    A consistent inspection sequence helps you cover every required area. Familiarity or a clean appearance does not show that the vehicle is safe.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.1.5, physical PDF 31, printed 2-3. ↗

  2. During a truck walk-around, rusty streaks lead away from several wheel nuts. What do they suggest?

    Correct answer: The nuts may be loose and need their tightness checked

    Rust around wheel nuts can signal movement from looseness. Check the wheel fastening condition rather than treating the streaks as merely cosmetic.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.1.3, physical PDF 30, printed 2-2. ↗

  3. A damaged exhaust connection is allowing fumes near your truck cab. Why does it need attention before the trip?

    Correct answer: Exhaust can enter the cab or sleeper and poison occupants

    A leaking exhaust system can carry poisonous fumes into occupied areas. Repair the defect; closing off the sleeper is not protection from fumes.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.1.3, physical PDF 31, printed 2-3. ↗

  4. Your trip paperwork and a heavy tool are lying loose beside the pedals. What should you do before moving?

    Correct answer: Stow them securely so they cannot obstruct the controls

    Loose cab objects can interfere with pedals or strike someone during a sudden stop. Secure them before starting.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.1.5, physical PDF 35, printed 2-7. ↗

  5. During the guide's stationary hydraulic-brake check, the pedal continues to sink under firm pressure. What is the appropriate response?

    Correct answer: Have the brake problem corrected before driving

    A pedal that moves while held firmly can indicate a leak or another hydraulic fault. This is a defect to correct before operating, not a normal warm-up condition.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.1.5, physical PDF 35, printed 2-7. ↗

  6. For a truck subject to 49 CFR 393.75, which pair gives the minimum major-groove tread depths for front tires and other tires?

    Correct answer: 4/32 inch at the front; 2/32 inch on the other tires

    Measure major grooves, excluding tie bars, humps and fillets. These are minimum depths, not a guarantee that a tire with other damage is safe.

    Source: 49 CFR 393.75(b)-(c); tread depth and measurement exclusions. ↗

  7. A truck tire has adequate tread depth but its tread is separating from the casing. Can it be used for the planned highway trip?

    Correct answer: No; tread separation makes the tire unacceptable for operation

    The tire rule separately prohibits tread or sidewall separation. Adequate remaining tread does not cure that defect.

    Source: 49 CFR 393.75(a)(2); tread or sidewall separation. ↗

  8. Your truck's safety belt latches, but the webbing is badly frayed. Which conclusion is correct?

    Correct answer: The belt needs attention; latching alone does not make it sound

    The inspection includes the mounting, adjustment, latch and webbing. A ripped or frayed belt is not made serviceable just because its buckle clicks.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.1.5, physical PDF 32, printed 2-4. ↗

  9. Your drive tires begin spinning as you accelerate a heavy truck on a slick surface. How should you respond?

    Correct answer: Ease off the accelerator to reduce wheelspin

    Excess power can overwhelm the available traction. Reduce it, then use smooth, gradual acceleration suited to the surface.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.2.1, physical PDF 36, printed 2-8. ↗

  10. Two safe approaches to a loading area are available. Why is backing toward the driver's side generally preferred?

    Correct answer: It provides a better view of the vehicle's rear path

    Driver-side backing improves visibility, including the view through the side window. Both mirrors and checks of the whole path still matter.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.2.4, physical PDF 36, printed 2-8. ↗

  11. Before reversing under a loading canopy, you cannot judge its clearance from the cab. What should you do?

    Correct answer: Stop, get out and check the planned path and overhead space

    Check the full backing route, including overhead and side clearance, before moving. If uncertain during the maneuver, stop and check again.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.2.4, physical PDF 36, printed 2-8. ↗

  12. A helper is about to guide your truck into a bay. What must the two of you agree on before backing?

    Correct answer: A clear set of signals, especially the signal to stop

    Both people need to understand the signals before the truck moves. The helper must be visible to the driver; a stop signal is particularly important.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.2.4, physical PDF 36, printed 2-8. ↗

  13. Which transmission generally calls for double-clutching to shift gears in the guide's manual-transmission procedure?

    Correct answer: An unsynchronized heavy-vehicle manual transmission

    Most unsynchronized heavy-vehicle manuals need double-clutching. Synchronized manuals do not require it; learn the procedure for the actual vehicle.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.3.1, physical PDF 37, printed 2-9. ↗

  14. You are approaching a long downgrade in a loaded truck. When should you select the appropriate low gear?

    Correct answer: Before starting down, while speed is still controlled

    Slow and select the right gear before the descent. Waiting until speed builds can make a downshift impossible and remove engine braking when it is most needed.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.3.1, physical PDF 37, printed 2-9. ↗

  15. You switch to a truck with a different engine and gearbox. How should you decide the proper upshift range?

    Correct answer: Use that vehicle's operating instructions and tachometer

    Shift ranges depend on the vehicle. Learn the recommended engine-speed or road-speed ranges instead of assuming all trucks share one setting.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.3.1, physical PDF 37, printed 2-9. ↗

  16. The road becomes icy while your truck's speed retarder is engaged. What does the CDL guide advise?

    Correct answer: Turn the retarder off because drive wheels may skid

    Retarding force at the drive wheels can exceed available grip on slippery roads. The guide directs drivers to switch it off on wet, icy or snow-covered surfaces.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.3.4, physical PDF 38, printed 2-10. ↗

  17. For routine road scanning, how far ahead does the CDL guide recommend looking while also checking nearer conditions?

    Correct answer: About 12 to 15 seconds of travel ahead

    The look-ahead recommendation gives time to spot changes and plan. It is a scanning distance, not the following-gap formula.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.4.1, physical PDF 38, printed 2-10. ↗

  18. A vehicle looks small and distant in your truck's convex mirror. What should you remember before moving sideways?

    Correct answer: It may be closer than the mirror image makes it appear

    Convex mirrors show a wider area but make objects look smaller and farther away. Account for this distortion when judging nearby traffic.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.4.2, physical PDF 39, printed 2-11. ↗

  19. You checked the mirrors and then signaled a lane change, but have not moved yet. Why check again?

    Correct answer: Another vehicle may have entered the space or a blind spot

    Traffic positions change quickly. The guide calls for checks before the maneuver, after signaling, as movement begins and after completion.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.4.2, physical PDF 39, printed 2-11. ↗

  20. You complete a right turn in a truck whose indicator does not cancel automatically. What should you do next?

    Correct answer: Cancel it so others are not misled about your next move

    A signal left on after the turn sends a false message. Keep it on through the turn, then cancel it once the maneuver is complete.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.5.1, physical PDF 39, printed 2-11. ↗

  21. A car driver behind your truck asks you to wave them past. What is the safer response?

    Correct answer: Do not signal that passing is safe; let that driver assess it

    Do not take responsibility for directing another driver's pass. They may face hazards you cannot assess from the truck.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.5.1, physical PDF 40, printed 2-12. ↗

  22. Your interstate CMV breaks down on a rural highway shoulder where warning devices are required. When should you place them?

    Correct answer: As soon as possible, and within 10 minutes

    Activate hazard flashers immediately. Place the required warning devices promptly; ten minutes is the outside limit, not a waiting period.

    Source: 49 CFR 392.22(a), (b)(1); breakdown outside municipal exceptions. ↗

  23. On a straight, level rural divided-highway shoulder, how should you arrange the three required triangles behind a disabled CMV?

    Correct answer: One within 10 feet on its traffic side; others about 100 and 200 feet toward approaching traffic

    For a divided or one-way road, warn traffic approaching from the rear. The nearest device is on the traffic side; the farther two follow the occupied lane or shoulder.

    Source: 49 CFR 392.22(b)(2)(v); unobstructed divided highway, no municipal exception. ↗

  24. When estimating total stopping space, why is the distance traveled before touching the brake important?

    Correct answer: Perception and reaction travel are added to braking travel

    The truck continues moving while the driver notices a hazard and reacts. Total stopping space includes that travel as well as the braking distance.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.6.1, physical PDF 41, printed 2-13. ↗

  25. Under comparable ideal conditions, doubling speed has roughly what effect on braking distance alone?

    Correct answer: It increases to about four times as much

    The guide uses a squared relationship for braking distance: twice the speed means roughly four times the braking distance. This is not a promise about total stopping distance in real conditions.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.6.1, physical PDF 42, printed 2-14. ↗

  26. Your tall loaded truck approaches a signed curve. Does the posted curve speed guarantee that your truck will not roll over?

    Correct answer: No; its load and high center of gravity may require a lower speed

    A top-heavy truck can roll even when its tires retain grip. Select a safe speed before entering, taking the vehicle and load into account.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.6.3, physical PDF 43, printed 2-15. ↗

  27. On an unlit highway, your stopping distance would extend beyond the area your low beams reveal. What adjustment is needed?

    Correct answer: Reduce speed so you can stop within the visible distance

    You need enough visible road to stop for a hazard. Driving beyond the effective headlight range leaves too little warning time.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.11.4, physical PDF 54, printed 2-26. ↗

  28. After a dry spell, light rain has just begun on the highway. Why can the surface be particularly slick?

    Correct answer: Water mixes with oil and residue already on the pavement

    Initial rain can mix with accumulated road deposits before heavier rain washes them away. Reduce speed and allow more room.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.6.2, physical PDF 42, printed 2-14. ↗

  29. Near freezing, the pavement looks wet but the surface may actually be a thin transparent frozen layer. What is this hazard?

    Correct answer: Black ice

    Black ice can resemble a wet roadway. Do not assume the shiny surface offers ordinary wet-road traction.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.6.2, physical PDF 42, printed 2-14. ↗

  30. What happens when a truck hydroplanes in standing water?

    Correct answer: A water layer reduces the tires' contact with the road

    Hydroplaning reduces tire contact and traction, limiting both steering and braking control. Slow beforehand and avoid standing water where possible.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.6.2, physical PDF 42, printed 2-14. ↗

  31. In good conditions at 35 mph, what starting gap follows the guide's one-second-per-10-feet rule for a 40-foot truck?

    Correct answer: At least 4 seconds

    Forty feet gives four seconds at this speed. Add more space for poor traction, visibility or other hazards; this is a baseline safety guideline.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.7.1, physical PDF 44, printed 2-16. ↗

  32. For a 60-foot combination at 55 mph in good conditions, what baseline gap follows the guide's length-and-speed rule?

    Correct answer: At least 7 seconds

    Allow one second per ten feet, then add one second above 40 mph: six plus one is seven. Conditions can require a still larger gap.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.7.1, physical PDF 44, printed 2-16. ↗

  33. A car is following your truck too closely. Which change helps you avoid a sudden stop that it may not handle?

    Correct answer: Increase the space ahead and slow gradually when needed

    More space ahead lets you respond more gradually. Do not use brake-checking or increased speed to deal with a tailgater.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.7.2, physical PDF 45, printed 2-17. ↗

  34. A van trailer cleared a low structure while loaded. After unloading, is that earlier clearance enough proof for the return trip?

    Correct answer: No; the unloaded vehicle can sit higher, so clearance must be checked

    Suspension height can increase after unloading. Know the current vehicle height and actual available clearance instead of relying on the earlier passage.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.7.4, physical PDF 45, printed 2-17. ↗

  35. Your low trailer approaches a sharply raised railroad crossing. What must you consider before entering?

    Correct answer: Whether its underside could hang up before it clears the tracks

    Low ground clearance and a steep crossing profile can trap a trailer on the rails. Do not enter unless the vehicle can clear the crossing safely.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.7.5, physical PDF 45, printed 2-17. ↗

  36. Why is swinging left before starting a wide right turn hazardous in a large truck?

    Correct answer: A following driver may enter the opening along your right side

    The opening and apparent leftward movement can invite a vehicle onto your right. Plan the turn to protect that space and monitor it carefully.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.7.6, physical PDF 46, printed 2-18. ↗

  37. You must cross a road with a heavily loaded truck. Compared with a car, what should you plan for?

    Correct answer: A larger gap because acceleration and full clearance take longer

    A long, heavy vehicle needs time and space to accelerate and clear the entire road. Do not start unless the whole vehicle can cross safely.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.7.7, physical PDF 46, printed 2-18. ↗

  38. A cardboard box lies in your truck's lane. What is the prudent assumption while planning a safe response?

    Correct answer: It may contain something heavy enough to damage the vehicle

    The contents are unknown. Spot debris early so you can avoid it without an abrupt, unsafe maneuver.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.8.2, physical PDF 47, printed 2-19. ↗

  39. A car entering an exit lane suddenly brakes and hesitates. What possible action should you prepare for?

    Correct answer: It may return unexpectedly to the through lane

    Hesitation near an exit can precede a sudden change of direction. Create time and space before the developing hazard becomes an emergency.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.8.1, physical PDF 46, printed 2-18. ↗

  40. You need directions for a new delivery location. When is the best time to enter the route into your navigation system?

    Correct answer: Before moving, with the truck safely parked

    Set up the route before driving. If you later need to change it, find a safe place to stop instead of dividing attention in traffic.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.9.6, physical PDF 51, printed 2-23. ↗

  41. An angry driver repeatedly gestures and tries to get ahead of your truck. What is the safest response?

    Correct answer: Give them room and avoid answering the challenge

    Avoid escalating the confrontation. Keep driving safely, create separation and let the aggressive driver move away.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.10.3, physical PDF 52, printed 2-24. ↗

  42. You have heavy eyelids and cannot remember the last few miles of your truck route. What should you do?

    Correct answer: Stop at a safe place and get sleep before continuing

    These are warning signs of fatigue. Noise, cool air or stimulants do not replace sleep or reliably make continued driving safe.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.11.2, physical PDF 53, printed 2-25. ↗

  43. While seeking a safe place to stop in fog, which headlights should you use?

    Correct answer: Low beams

    Low beams reduce reflected glare and help others see the truck. Reduce speed before visibility worsens and leave the roadway for a safe stopping place when needed.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.12, physical PDF 55, printed 2-27. ↗

  44. In dense fog, why should you not simply follow a pair of taillights as your guide to the roadway?

    Correct answer: They may belong to a vehicle stopped off the road

    Lights ahead may be on the shoulder or outside the travel lane. Do not substitute another vehicle's position for your own assessment of the road.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.12, physical PDF 55, printed 2-27. ↗

  45. Before climbing into a truck after freezing rain, what should you clear as well as the windows?

    Correct answer: Ice and snow from the steps, handholds and deck plates

    Icy access surfaces can cause a fall before the trip even begins. Clear them while also completing the winter vehicle checks.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.13.1, physical PDF 56, printed 2-28. ↗

  46. After highway driving in hot weather, tire pressure is higher than its correct cold setting. What should you avoid?

    Correct answer: Bleeding air merely to restore the cold-pressure reading

    Heat raises inflation pressure. Releasing air to the cold setting while the tire is hot can leave it underinflated once it cools.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.14.1, physical PDF 57, printed 2-29. ↗

  47. The engine coolant is very hot. What is the safe approach to a radiator cap that is part of the pressurized system?

    Correct answer: Leave it closed until the system has cooled

    Hot pressurized coolant and steam can cause severe burns. Shutting the engine off does not instantly cool or depressurize the system.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.14.1, physical PDF 57, printed 2-29. ↗

  48. After water enters brake drums, how can braking performance change?

    Correct answer: Brakes may weaken, grab or apply unevenly

    Wet brakes can behave unpredictably, including weakness or uneven application. Avoid deep water and do not assume normal braking remains available.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.13.2, physical PDF 56, printed 2-28. ↗

  49. One train has cleared a crossing with two tracks. What hazard remains before your truck proceeds?

    Correct answer: Another train may have been hidden on the second track

    Check every track and obey the crossing controls. A passing train can hide another approaching train.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.15.3, physical PDF 59, printed 2-31. ↗

  50. You have a clear path across the railroad tracks in a manual-transmission truck. How should you handle the gear selection?

    Correct answer: Choose a suitable gear beforehand and avoid shifting on the tracks

    Avoid a missed shift or loss of drive while occupying the crossing. Be sure the whole vehicle can clear before entering.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.15.5, physical PDF 59, printed 2-31. ↗

  51. On a long descent, repeated heavy service-brake use produces less slowing despite more pedal pressure. What may be happening?

    Correct answer: The brakes are overheating and fading

    Excess heat can reduce braking effectiveness. Proper gear and speed selection help avoid relying too heavily on the service brakes.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.16.3, physical PDF 60, printed 2-32. ↗

  52. On a dry downgrade, the truck is in the proper low gear and 35 mph is your selected safe speed. Under the guide's braking technique, when do you release an application begun at 35 mph?

    Correct answer: After slowing to about 30 mph

    The described technique supplements engine braking: make a definite slowdown to about five mph below the selected safe speed, release, and repeat when speed returns to that safe value.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.16.4, physical PDF 60, printed 2-32. ↗

  53. Your truck's brakes fail on a descent and a marked escape ramp is available. What should you do?

    Correct answer: Use the ramp instead of hoping the next stretch will stop you

    Escape ramps are intended to stop runaway vehicles. Delaying after brake failure allows speed and danger to increase.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.17.3, physical PDF 62, printed 2-34. ↗

  54. A front tire suddenly blows out and no collision is immediately unavoidable. What is the guide's first control advice?

    Correct answer: Grip the wheel firmly and avoid braking until speed drops

    Maintain directional control and avoid the hard braking that can worsen a blowout. Once slowed, brake gently, pull off safely and check the tires.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.17.4, physical PDF 63, printed 2-35. ↗

  55. You must make an emergency stop in a straight truck with functioning ABS on every axle. Which action does the guide permit?

    Correct answer: Fully apply the brakes while maintaining control

    The guide expressly allows full application for an emergency stop with working ABS on all axles. This is not the same as advice for a combination with ABS on only part of it.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.18.6, physical PDF 64, printed 2-36. ↗

  56. Which benefit should you expect from functioning ABS during hard braking?

    Correct answer: Reduced wheel lockup and improved ability to retain control

    ABS manages wheel lockup. It may help maintain steering and stability without necessarily shortening the stop.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.18, physical PDF 63, printed 2-35. ↗

  57. A loaded truck has ABS. Does that make taking a curve too fast safe?

    Correct answer: No; ABS does not prevent skids or rollover from excessive cornering speed

    ABS addresses brake-induced wheel lockup. It cannot supply extra cornering grip or cancel the effects of an excessive speed and high center of gravity.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.18.8, physical PDF 64, printed 2-36. ↗

  58. The ABS malfunction lamp comes on while driving, but there is no indication that the regular brakes have failed. What does that lamp mean?

    Correct answer: ABS assistance may be lost; regular braking remains, and the fault needs service

    An ABS fault does not by itself mean loss of the normal brake system. Maintain safe braking and arrange service; respond separately to any actual brake fault.

    Source: Washington Commercial Driver Guide, N/10/20; section 2.18.7, physical PDF 64, printed 2-36. ↗

  59. After stopping safely, you suspect a fire under the truck's hood. Should you open it to inspect the flames?

    Correct answer: No; opening it can feed the fire and make it grow

    Keep the hood closed, shut off the engine after stopping, evacuate and call emergency services. Do not approach or reopen the burning vehicle.

    Source: US Fire Administration, Vehicle Fire Safety; if your vehicle catches fire. ↗

  60. Everyone has escaped a burning truck. Where should you gather while calling 911?

    Correct answer: At least 100 feet away and well clear of traffic

    USFA advises moving everyone at least 100 feet from a burning vehicle and away from traffic. Stay out and let emergency responders handle the fire.

    Source: US Fire Administration, Vehicle Fire Safety; evacuation distance and emergency notification. ↗

  61. Warehouse staff load and secure your truck while you complete paperwork. Does that remove your responsibility for the load?

    Correct answer: No; you still need to assure yourself it is safely distributed and secured

    The driver remains responsible for safe cargo, even when someone else performs the loading. Check securement, balance and safe access before the trip.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.1, physical PDF 72, printed 3-1. ↗

  62. A firmly tied load blocks your access to the truck's emergency equipment. Is its arrangement acceptable?

    Correct answer: No; secure cargo must also leave ready access to emergency equipment

    A load can be firmly secured and still be unsafe because it obstructs emergency access, controls or vision. Correct the arrangement before driving.

    Source: 49 CFR 392.9(a)(3); emergency access and cab obstructions. ↗

  63. You start a trip with accessible cargo in an interstate truck; no inspection exception applies. When must you first recheck its securement on the road?

    Correct answer: Within the first 50 miles

    Inspect within the first 50 miles and make needed adjustments. The later reinspection intervals do not replace this initial check.

    Source: 49 CFR 392.9(b)(2), (b)(4); initial check with sealed/impracticable exceptions excluded. ↗

  64. With accessible cargo and no exception, you have driven 3 hours but only 110 miles since the last cargo recheck. What is required?

    Correct answer: Reexamine the load now; the three-hour trigger has been reached

    For applicable trucks, recheck when duty status changes, after three driving hours or after 150 miles, whichever comes first. The mileage limit does not postpone a time-based check.

    Source: 49 CFR 392.9(b)(3); duty change, 3 hours or 150 miles, whichever first. ↗

  65. You change duty status after a short drive with an inspectable load. Neither 3 hours nor 150 miles has elapsed. Does the cargo rule still require a recheck?

    Correct answer: Yes; a duty-status change is a separate reexamination trigger

    The rule lists duty-status changes as well as time and distance. An applicable driver does not need to wait for the other thresholds.

    Source: 49 CFR 392.9(b)(3)(i); duty-status-change trigger, no inspection exception. ↗

  66. Your trailer is sealed and you have been ordered not to open it for inspection. What remains important despite that inspection exception?

    Correct answer: Check gross and axle weights and the vehicle's external condition

    The sealed-load exception does not certify safe weights or the condition of the vehicle. Respect the seal and verify the checks that remain possible, including gross and axle loads.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.3.5, physical PDF 74, printed 3-3. ↗

  67. A loaded truck is within its overall weight limit, but cargo is concentrated over one axle. What must be checked?

    Correct answer: Individual axle loading as well as the total vehicle weight

    An acceptable total does not prove acceptable axle loading or balance. Load distribution affects both equipment limits and handling.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.2.4, physical PDF 73, printed 3-2. ↗

  68. When arranging heavy and light freight, which layout generally lowers rollover risk?

    Correct answer: Place the heavier freight low and the lighter freight above it

    Keeping heavy cargo low reduces the center of gravity. High stacks and heavy freight on top increase instability in curves or evasive moves.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.2.3, physical PDF 73, printed 3-2. ↗

  69. Too much cargo weight is shifted toward the back, leaving the front axle too lightly loaded. What can result?

    Correct answer: Reduced steering traction and unsafe directional control

    The steering axle needs suitable loading for traction and control. Moving weight rearward without checking balance can make steering unsafe.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.2.4, physical PDF 73, printed 3-2. ↗

  70. Your truck has too little weight on its drive axles for the conditions. Which difficulty is more likely?

    Correct answer: Drive-wheel spin and reduced traction

    Drive tires need adequate traction to move the load. Too little drive-axle weight can make wheelspin especially troublesome in bad weather.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.2.4, physical PDF 73, printed 3-2. ↗

  71. You secure shaped blocks snugly against a crate and fasten them to the deck. What is their main purpose?

    Correct answer: Prevent the crate from sliding along the load deck

    Blocking restrains movement at the cargo's sides, front or rear. Its installation and strength must suit the load; other applicable securement requirements still matter.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.3.1, physical PDF 73, printed 3-2. ↗

  72. Under the general article-securement rule, what minimum aggregate working load limit is needed for an 8,000-pound article?

    Correct answer: 4,000 pounds

    The aggregate WLL minimum is half the article's weight: 8,000 divided by two. Count and arrangement rules must also be met, and a tiedown's contribution depends on how it is attached.

    Source: 49 CFR 393.106(d); aggregate working-load limit, general article rule. ↗

  73. Under the general tiedown-count rule, an unblocked 4-foot, 900-pound article needs at least how many tiedowns? Assume adequate strength and no special commodity rule.

    Correct answer: One tiedown

    For an article no longer than five feet and no heavier than 1,100 pounds, the unblocked general rule permits one as the count minimum. Strength and securement requirements still apply.

    Source: 49 CFR 393.110(b)(1); short/light unblocked article, general count rule. ↗

  74. An 8-foot article weighs only 500 pounds and is not blocked against forward movement. Under the general rule, what is the minimum tiedown count?

    Correct answer: Two tiedowns

    An unblocked article longer than five feet and no longer than ten feet needs at least two, regardless of its low weight. This assumes no commodity-specific rule and sufficient securement strength.

    Source: 49 CFR 393.110(b)(2)(ii); over 5 through 10 feet, unblocked. ↗

  75. A 12-foot article is not blocked against forward movement. Under the general tiedown-count rule, how many are needed at minimum?

    Correct answer: Three tiedowns

    For an unblocked article longer than ten feet, use two for the first ten feet plus one for the remaining fraction. This is the count minimum, with strength and other applicable requirements separate.

    Source: 49 CFR 393.110(b)(3); unblocked 12-foot article, no special-method exception. ↗

  76. A 12-foot article is properly blocked against forward movement. Under the general rule, what is its minimum tiedown count, assuming no special rule applies?

    Correct answer: Two tiedowns

    Properly blocked articles require at least one tiedown per ten feet or fraction. Twelve feet therefore needs two; adequate blocking, strength and attachment remain necessary.

    Source: 49 CFR 393.110(c); blocked 12-foot article, no special-method exception. ↗

  77. Your tiedowns meet the minimum count, but their calculated aggregate WLL is below the required amount. Is the cargo ready to travel?

    Correct answer: No; both the count and strength requirements must be met

    The requirements work together. Enough tiedowns by number may still provide insufficient rated restraint for the load.

    Source: 49 CFR 393.110(a), referring to 393.106; count requirements are additional. ↗

  78. Why must a truck's front-end header board be sound and properly secured?

    Correct answer: It helps resist cargo moving forward during a sudden stop

    A header board protects the front of the cargo area against forward load movement. A damaged structure may not provide that restraint.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.3.3, physical PDF 74, printed 3-3. ↗

  79. A tarp covers freight on a flatbed. What still needs to be established before driving?

    Correct answer: That the cargo itself is properly secured against movement

    A cover can protect against weather or spillage, but it does not automatically provide the restraint needed to secure the cargo. Secure the load and the cover.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.3.4, physical PDF 74, printed 3-3. ↗

  80. Why does a refrigerated trailer carrying hanging meat call for particular caution on a curved exit ramp?

    Correct answer: The suspended load can be unstable and has a high center of gravity

    Hanging cargo can be unstable and top-heavy. Enter curves slowly and avoid abrupt control changes that can disturb the load.

    Source: Washington Commercial Driver Guide, N/10/20; section 3.4.2, physical PDF 74, printed 3-3. ↗

Report a problem with this question

Question reference: wa-cdl-general-001

Opens a draft in your email app. Review and send it there; nothing is sent automatically.

Draft a correction email

Contact details & help

Study tools & test information

Home / Washington / CDL

Washington CDL practice questions

All 80 general-driving and cargo questions in one untimed practice. This is the current selection, not the complete CDL manual or endorsement coverage.

All topics and study tools