DMV Practice LabChange state
TXTexas
DMV Practice LabAll tests

Texas CDL: General Knowledge

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

Texas CDL General Knowledge

Practice mode
Question 1 of 100
  1. 1. Who is ultimately responsible for the safe operation of a commercial vehicle after an inspection?
  2. 2. Which items should a commercial driver monitor during a trip for signs of trouble?
  3. 3. What minimum tread depth is required in every major groove of a commercial vehicle’s front tires?
  4. 4. Which tire placement is prohibited on the front wheels of a bus?
  5. 5. What can rust around a commercial vehicle’s wheel nuts indicate?
  6. 6. Why is excessive steering-wheel play a serious inspection defect?
  7. 7. Which warning equipment is a standard option for a parked commercial vehicle?
  8. 8. During the CDL vehicle inspection test, what must an applicant do when identifying an item?
  9. 9. What is the principal method for controlling speed on a long downgrade?
  10. 10. When should a commercial driver select the proper low gear for a downgrade?
  11. 11. How should speed be chosen when fog or darkness limits the view ahead?
  12. 12. Under the handbook length rule below 40 mph, what is the minimum following time for a 50-foot commercial vehicle?
  13. 13. What extra following time should be added when traveling above 40 mph?
  14. 14. How should a commercial driver respond to a vehicle following too closely?
  15. 15. Why might an empty cargo van require more overhead clearance than the same van when loaded?
  16. 16. When a large vehicle needs extra room to complete a right turn, what should the driver avoid doing at the start?
  17. 17. Who is responsible for recognizing an overload or poorly balanced cargo?
  18. 18. For an accessible, unsealed truck load, when must the driver first recheck cargo securement after starting the trip?
  19. 19. After the initial check of an accessible, unsealed truck load, when is the next cargo reinspection required?
  20. 20. What does a single vehicle’s gross vehicle weight rating (GVWR) represent?
  21. 21. Where should the heaviest cargo generally be placed to reduce rollover risk?
  22. 22. What can result from placing too little weight on the front axle?
  23. 23. What aggregate working load limit must a cargo securement system provide?
  24. 24. Under the general federal tie-down rule, a 7-foot article is not blocked against forward movement. What is the minimum number of tie-downs?
  25. 25. Why should a driver check cargo covers in the mirrors while traveling?
  26. 26. You must back into an unfamiliar loading space. What should you do before beginning the maneuver?
  27. 27. While backing slowly, you become unsure whether the right rear corner will clear an obstacle. What is the safest next step?
  28. 28. Before backing with a helper, which signal should you both agree on?
  29. 29. The drive wheels begin spinning as you accelerate from a stop on a snowy road. What response does the handbook recommend?
  30. 30. You are approaching a curve in a commercial vehicle with a manual transmission. When should you reduce speed and select the appropriate lower gear?
  31. 31. A vehicle appears small and distant in your convex mirror. What should you remember before judging the available gap?
  32. 32. Before a trip with a trailer, which position allows an accurate check of mirror adjustment?
  33. 33. You are looking 12 to 15 seconds ahead as recommended for commercial driving. How should you also monitor the nearer road?
  34. 34. What is the safest way to make routine mirror checks while traveling?
  35. 35. Before departure, why should you secure loose tools and other articles in the cab?
  36. 36. A following driver wants to pass your truck. Should you wave them around as a guarantee that the road is clear?
  37. 37. Your commercial vehicle must stop on the highway shoulder. How soon must required emergency warning devices be placed?
  38. 38. On a straight divided highway with a clear view, what spacing does the handbook give for the three warning devices behind a stopped truck?
  39. 39. A truck stops beside a straight two-way road with clear sightlines. Why are warning devices needed both ahead and behind?
  40. 40. At dusk in rain, are identification and clearance lights alone sufficient to make your truck visible?
  41. 41. You keep your hands on the wheel but become absorbed in a stressful conversation. What type of distraction can this create?
  42. 42. When is the best time to program the route into your navigation system?
  43. 43. A car ahead drifts within its lane while its driver looks down repeatedly. How should you react?
  44. 44. An aggressive driver tries to provoke you. What is the safer response?
  45. 45. Snow covers the truck’s mirrors and side windows before departure. What is required for a safe start?
  46. 46. Why is a leaking exhaust especially dangerous when the cab windows are closed?
  47. 47. After water enters a truck’s brakes, what behavior can occur?
  48. 48. A properly inflated tire’s pressure rises during hot-weather operation. Should you bleed air to its cold-pressure reading?
  49. 49. During a hot-weather stop, a tire is too hot to touch. What does the handbook direct you to do?
  50. 50. When is it safe to open the pressurized radiator system for a coolant check?
  51. 51. Dark patches of tar have risen to the road surface in extreme heat. What hazard should you expect?
  52. 52. How should a manual-transmission truck cross railroad tracks?
  53. 53. One train has passed a crossing with two tracks. What must you check before proceeding?
  54. 54. A railroad crossing has no active lights or gates. What does that mean for your decision?
  55. 55. Why is listening for a horn alone an unsafe crossing check?
  56. 56. The front wheels slide and the truck continues straight despite steering input. What should you avoid?
  57. 57. Excessive braking has locked the rear drive wheels of a truck without effective ABS intervention. What is the first recovery action?
  58. 58. After a collision, you are uninjured and able to act. What is an immediate priority?
  59. 59. You stop to help at a collision in which your truck was not involved. Where should you park?
  60. 60. Smoke indicates a vehicle fire while you are driving. Where should you stop if you can safely move off the road?
  61. 61. Why should you avoid opening the hood fully during an engine fire?
  62. 62. Smoke comes from a closed box trailer, and the cargo may be hazardous. Should you open its doors to investigate?
  63. 63. For a small fire you can safely tackle with the correct extinguisher and an escape path, where should you aim?
  64. 64. You do not know which extinguishing agent is safe for the burning cargo. What should you do?
  65. 65. A B:C extinguisher is intended for which hazards?
  66. 66. What is the purpose of blocks secured snugly around cargo?
  67. 67. What does bracing between upper cargo and the compartment structure help prevent?
  68. 68. Why inspect a front-end header board before carrying a load?
  69. 69. You are ordered not to open a sealed load. Which duty still remains?
  70. 70. What makes a dry-bulk tank load demanding in a sharp curve?
  71. 71. Why is suspended meat cargo a special concern on an off-ramp?
  72. 72. How can live animals affect trailer stability?
  73. 73. Before moving an oversize or overweight load, what arrangements should you establish?
  74. 74. What does axle weight measure?
  75. 75. Your load is within the legal maximum. Does that guarantee it is safe for bad weather or a mountain route?
  76. 76. How should you determine suitable shift points for an unfamiliar commercial vehicle?
  77. 77. Why does the handbook advise turning a retarder off on a slippery road?
  78. 78. An approaching driver leaves bright lights on. What should you do?
  79. 79. Why clean both sides of the windshield before a night trip?
  80. 80. Your eyelids are heavy and you are struggling to stay alert. What is the safe response?
  81. 81. You see dense fog ahead while approaching a safe truck stop. What is the preferable choice?
  82. 82. Why should you avoid using another vehicle’s taillights as your only guide through fog?
  83. 83. When should you learn how to fit the chains carried for your drive tires?
  84. 84. Which combination matters when selecting a safe descent speed?
  85. 85. Your truck’s brakes have failed on a downgrade and an escape ramp is available. What should you do?
  86. 86. A hydraulic service-brake pedal goes to the floor. Which action may briefly restore hydraulic pressure?
  87. 87. A truck tire fails, but there is no immediate collision ahead. What is the initial response?
  88. 88. Does buying a cold medicine without a prescription prove it is safe before commercial driving?
  89. 89. You become too ill to operate your truck safely. What should you do?
  90. 90. Why must a commercial driver keep hazardous-material shipping papers readily accessible?
  91. 91. Your vehicle was operating normally yesterday. What inspection is needed for the next trip?
  92. 92. A hot engine has a see-through coolant reservoir with level markings. How can you check the level without opening the hot system?
  93. 93. A breakdown forces your truck to stop on the highway shoulder. Which lights should you switch on immediately to warn approaching traffic?
  94. 94. In its basic steering-defect guidance, what amount of steering-wheel free play does the Texas CDL handbook warn can make steering difficult?
  95. 95. A freight container is designed to transfer between a truck chassis, a train and a ship. What kind of container is it?
  96. 96. Why should a driver not use water on burning gasoline or energized electrical equipment?
  97. 97. Before adding the separate air-brake lag factor where applicable, which three distances make up the handbook’s basic stopping-distance model?
  98. 98. A newer streamlined truck climbed a hill in a relatively high gear. Should you automatically use that same gear to descend?
  99. 99. Two legal parking spaces are equally suitable for your truck. One allows a forward exit; the other requires backing into traffic. Which is preferable?
  100. 100. Why check the rated capacity of a coupling device before assigning a load?
Review all 100 questions with answers

  1. Who is ultimately responsible for the safe operation of a commercial vehicle after an inspection?

    Correct answer: The driver

    The driver remains responsible for operating the vehicle safely, even when maintenance personnel performed repairs.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 28: Vehicle inspection ↗

  2. Which items should a commercial driver monitor during a trip for signs of trouble?

    Correct answer: Gauges and the vehicle through sight, sound, smell, and feel

    Trip inspection includes watching gauges and using the senses to detect developing problems.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 28: Vehicle inspection ↗

  3. What minimum tread depth is required in every major groove of a commercial vehicle’s front tires?

    Correct answer: 4/32 inch

    Front tires require at least 4/32 inch; other tires require at least 2/32 inch.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 28: Tires ↗

  4. Which tire placement is prohibited on the front wheels of a bus?

    Correct answer: Regrooved, recapped, or retreaded tires

    A bus may not use regrooved, recapped, or retreaded tires on its front wheels.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 28: Tires ↗

  5. What can rust around a commercial vehicle’s wheel nuts indicate?

    Correct answer: The nuts may be loose

    Rust trails around wheel nuts can be evidence of movement and looseness.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 29: Wheels ↗

  6. Why is excessive steering-wheel play a serious inspection defect?

    Correct answer: It can make the vehicle difficult to steer

    Excessive play can prevent precise steering control and must be investigated.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 29: Steering ↗

  7. Which warning equipment is a standard option for a parked commercial vehicle?

    Correct answer: Three red reflective warning triangles

    Commercial emergency equipment includes approved warning devices such as three red reflective triangles.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 30: Emergency equipment ↗

  8. During the CDL vehicle inspection test, what must an applicant do when identifying an item?

    Correct answer: Point to or touch it, name it, and explain why it is inspected

    The inspection test requires identification of the component and an explanation of its safety purpose or condition.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 30: Vehicle inspection ↗

  9. What is the principal method for controlling speed on a long downgrade?

    Correct answer: Use the engine’s braking effect in a suitable low gear

    Selecting a low gear before descending lets engine braking control speed while preserving the service brakes.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 43: Speed management ↗

  10. When should a commercial driver select the proper low gear for a downgrade?

    Correct answer: Before starting down the grade

    The gear must be selected before descending because shifting later may be unsafe or impossible.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 43: Speed management ↗

  11. How should speed be chosen when fog or darkness limits the view ahead?

    Correct answer: So the vehicle can stop within the visible distance

    A driver must always be able to stop within the distance that can be seen clearly.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 42: Visibility ↗

  12. Under the handbook length rule below 40 mph, what is the minimum following time for a 50-foot commercial vehicle?

    Correct answer: 5 seconds

    The basic minimum is one second per 10 feet of vehicle length: five seconds for 50 feet. Leave more space when road, traffic, or weather conditions require it.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 43: Following distance ↗

  13. What extra following time should be added when traveling above 40 mph?

    Correct answer: One additional second

    Apply the length rule, then add one second when speed exceeds 40 mph.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 44: Following distance ↗

  14. How should a commercial driver respond to a vehicle following too closely?

    Correct answer: Increase the space ahead and avoid sudden changes

    More room ahead reduces the need for sudden braking and gives the tailgater an opportunity to pass.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 44: Tailgaters ↗

  15. Why might an empty cargo van require more overhead clearance than the same van when loaded?

    Correct answer: Its suspension may sit higher when empty

    Removing cargo can raise the vehicle, so a clearance that worked while loaded may no longer be sufficient.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 45: Overhead clearance ↗

  16. When a large vehicle needs extra room to complete a right turn, what should the driver avoid doing at the start?

    Correct answer: Swinging wide to the left

    A left swing can invite a following vehicle to pass on the right and enter the truck’s turning path.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 45: Right turns ↗

  17. Who is responsible for recognizing an overload or poorly balanced cargo?

    Correct answer: The driver

    The driver is responsible for inspecting the cargo and recognizing overloads, imbalance, and insecure loading.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 73: Cargo inspection ↗

  18. For an accessible, unsealed truck load, when must the driver first recheck cargo securement after starting the trip?

    Correct answer: Within the first 50 miles

    Inspect within the first 50 miles and correct any insecure loading. Separate exceptions apply to sealed loads the driver is ordered not to open and loads that cannot practicably be inspected.

    Source: 49 CFR 392.9(b): inspection intervals and sealed/inaccessible-load exceptions ↗

  19. After the initial check of an accessible, unsealed truck load, when is the next cargo reinspection required?

    Correct answer: At a duty-status change, 3 hours of driving, or 150 miles, whichever occurs first

    Recheck securement at the first of these events: a change of duty status, three driving hours, or 150 miles. Make needed adjustments before continuing.

    Source: 49 CFR 392.9(b): inspection intervals and sealed/inaccessible-load exceptions ↗

  20. What does a single vehicle’s gross vehicle weight rating (GVWR) represent?

    Correct answer: Its manufacturer-specified loaded weight rating

    GVWR is a rating specified by the manufacturer, not the actual scale reading for a particular trip.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 73: Cargo weight ↗

  21. Where should the heaviest cargo generally be placed to reduce rollover risk?

    Correct answer: As low as possible

    A lower center of gravity improves stability, especially in curves and emergency maneuvers.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 74: Cargo balance ↗

  22. What can result from placing too little weight on the front axle?

    Correct answer: The steering axle may be too light for safe steering

    Insufficient front-axle weight can reduce steering control.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 74: Cargo balance ↗

  23. What aggregate working load limit must a cargo securement system provide?

    Correct answer: At least one-half the weight of the secured article or group

    Aggregate working load limit must cover at least half the restrained cargo weight. Direct tie-downs count differently from tie-downs passing over or around cargo; do not simply add every strap rating.

    Source: FMCSA Cargo Securement Rules: Minimum Working Load Limit ↗

  24. Under the general federal tie-down rule, a 7-foot article is not blocked against forward movement. What is the minimum number of tie-downs?

    Correct answer: Two

    An unblocked article longer than 5 feet but shorter than 10 feet needs at least two tie-downs under the general rule. Required working load limit and any cargo-specific rules still apply.

    Source: FMCSA Cargo Securement Rules: Minimum Number of Tiedowns ↗

  25. Why should a driver check cargo covers in the mirrors while traveling?

    Correct answer: A loose cover can tear away, expose cargo, or block someone’s view

    A flapping cover can detach and create a visibility or roadway hazard.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Cargo covers ↗

  26. You must back into an unfamiliar loading space. What should you do before beginning the maneuver?

    Correct answer: Get out and examine the planned path, including side and overhead clearance

    Inspect the complete path before backing. Walking around lets you identify hazards and clearances that may not be visible from the driving position.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 36: Backing preparation ↗

  27. While backing slowly, you become unsure whether the right rear corner will clear an obstacle. What is the safest next step?

    Correct answer: Stop, secure the vehicle and get out to check the path

    If you are unsure of the path or clearance, stop and check it from outside the vehicle. Mirrors have blind spots, and moving slowly does not make uncertain clearance safe.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 36: Backing visibility ↗

  28. Before backing with a helper, which signal should you both agree on?

    Correct answer: A clear stop signal

    The helper must remain visible, and both people need to understand the hand signals. Section 2.2.4 specifically emphasizes agreeing on a stop signal.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 36: Backing control ↗

  29. The drive wheels begin spinning as you accelerate from a stop on a snowy road. What response does the handbook recommend?

    Correct answer: Ease off the accelerator to stop the wheel spin

    Too much power on a low-traction surface can make the drive wheels spin and cause loss of control. Remove your foot from the accelerator and use gradual acceleration suited to the available traction.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 35: Traction during acceleration ↗

  30. You are approaching a curve in a commercial vehicle with a manual transmission. When should you reduce speed and select the appropriate lower gear?

    Correct answer: Before entering the curve

    Slow to a safe speed and select the proper gear before the curve. This helps you maintain stable control rather than needing a gear change during the turn.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 37: Shifting before curves ↗

  31. A vehicle appears small and distant in your convex mirror. What should you remember before judging the available gap?

    Correct answer: The vehicle can be closer than its mirror image suggests

    Convex mirrors provide a wider view, but objects appear smaller and farther away than they really are. Allow for this distortion when judging traffic position.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 38: Convex mirrors ↗

  32. Before a trip with a trailer, which position allows an accurate check of mirror adjustment?

    Correct answer: With the tractor and trailer aligned straight

    Check mirror adjustment before the trip with the trailer straight. Showing part of your own vehicle provides a reference for judging other objects in the mirrors.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 38: Mirror adjustment ↗

  33. You are looking 12 to 15 seconds ahead as recommended for commercial driving. How should you also monitor the nearer road?

    Correct answer: Shift attention between distant and nearby conditions

    Looking well ahead does not replace monitoring nearby hazards. The handbook describes shifting attention back and forth between near and far to maintain awareness.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 37: Visual scanning ↗

  34. What is the safest way to make routine mirror checks while traveling?

    Correct answer: Use brief checks and return attention to the road ahead

    Frequent, brief mirror checks help you monitor surrounding traffic without traveling a long distance while looking away from the road ahead.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 38: Mirror use while driving ↗

  35. Before departure, why should you secure loose tools and other articles in the cab?

    Correct answer: They can obstruct controls or strike occupants during a collision

    Loose articles can interfere with vehicle controls or become impact hazards. Secure them before driving rather than relying on their current resting position.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 34: Cab safety ↗

  36. A following driver wants to pass your truck. Should you wave them around as a guarantee that the road is clear?

    Correct answer: No, let that driver make their own safe passing decision

    Do not direct other traffic into a pass; you cannot guarantee the maneuver will remain safe.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 39: Communication ↗

  37. Your commercial vehicle must stop on the highway shoulder. How soon must required emergency warning devices be placed?

    Correct answer: Within 10 minutes

    Use flashers immediately and place the required warning devices promptly.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 39: Roadside warning ↗

  38. On a straight divided highway with a clear view, what spacing does the handbook give for the three warning devices behind a stopped truck?

    Correct answer: 10, 100, and 200 feet toward approaching traffic

    All three warn traffic approaching from the direction serving that roadway. Adjust for an obstructed view.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 39: Roadside warning ↗

  39. A truck stops beside a straight two-way road with clear sightlines. Why are warning devices needed both ahead and behind?

    Correct answer: Traffic can approach the stopped vehicle from either direction

    The two-way layout includes warnings about 100 feet in each direction plus one close to the vehicle.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 40: Roadside warning ↗

  40. At dusk in rain, are identification and clearance lights alone sufficient to make your truck visible?

    Correct answer: No, use headlights too

    Clearance lamps do not replace headlights in reduced visibility.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 39: Visibility ↗

  41. You keep your hands on the wheel but become absorbed in a stressful conversation. What type of distraction can this create?

    Correct answer: Mental distraction from driving

    Attention can leave the driving task even when your eyes and hands appear correctly positioned.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 49: Distraction ↗

  42. When is the best time to program the route into your navigation system?

    Correct answer: Before beginning to drive

    Plan and set up navigation before moving rather than divide attention in traffic.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 51: Distraction ↗

  43. A car ahead drifts within its lane while its driver looks down repeatedly. How should you react?

    Correct answer: Leave extra room and anticipate an unexpected movement

    Recognizing distraction in another driver helps you protect your own space.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 51: Hazard awareness ↗

  44. An aggressive driver tries to provoke you. What is the safer response?

    Correct answer: Create separation and avoid challenging the driver

    Do not turn another driver’s aggression into a contest.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 51: Road rage ↗

  45. Snow covers the truck’s mirrors and side windows before departure. What is required for a safe start?

    Correct answer: Clear them as well as the windshield

    You need usable views around the vehicle before entering traffic.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 56: Winter inspection ↗

  46. Why is a leaking exhaust especially dangerous when the cab windows are closed?

    Correct answer: Carbon monoxide may accumulate in the cab

    Check exhaust defects; a closed cab can retain poisonous exhaust gases.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 56: Winter inspection ↗

  47. After water enters a truck’s brakes, what behavior can occur?

    Correct answer: Weak, uneven, or grabbing brake action

    Water can change braking behavior and contribute to wheel lock or pulling.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 56: Wet brakes ↗

  48. A properly inflated tire’s pressure rises during hot-weather operation. Should you bleed air to its cold-pressure reading?

    Correct answer: No, it could become underinflated when it cools

    Heat raises pressure; follow cold-inflation specifications rather than vent hot tires.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 56: Hot tires ↗

  49. During a hot-weather stop, a tire is too hot to touch. What does the handbook direct you to do?

    Correct answer: Remain stopped until it cools

    Continuing with an overheated tire increases the risk of failure or fire.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 56: Hot tires ↗

  50. When is it safe to open the pressurized radiator system for a coolant check?

    Correct answer: After it has cooled, following the vehicle’s instructions

    Hot pressurized coolant can cause severe burns. Engine shutdown alone does not release that danger.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 57: Cooling system ↗

  51. Dark patches of tar have risen to the road surface in extreme heat. What hazard should you expect?

    Correct answer: Reduced traction on the slick patches

    Heat-softened surface tar can be slippery.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 57: Hot-weather traction ↗

  52. How should a manual-transmission truck cross railroad tracks?

    Correct answer: Select an appropriate gear before crossing and do not shift on the tracks

    Avoid a missed shift or loss of movement where a train could approach.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 59: Railroad crossings ↗

  53. One train has passed a crossing with two tracks. What must you check before proceeding?

    Correct answer: Whether another train is approaching on either track

    A train can conceal another train. Obey warning devices and verify the crossing is clear.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 59: Railroad crossings ↗

  54. A railroad crossing has no active lights or gates. What does that mean for your decision?

    Correct answer: You must look and listen and determine that crossing is safe

    The absence of active warning equipment is not evidence that no train is coming.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 57: Railroad crossings ↗

  55. Why is listening for a horn alone an unsafe crossing check?

    Correct answer: Some trains do not sound a horn and cab noise may mask it

    Use active observation and obey crossing controls rather than rely on sound alone.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 59: Railroad crossings ↗

  56. The front wheels slide and the truck continues straight despite steering input. What should you avoid?

    Correct answer: Adding more harsh steering or braking

    A front-wheel skid needs traction recovery; greater steering force does not create grip.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 65: Skid recognition ↗

  57. Excessive braking has locked the rear drive wheels of a truck without effective ABS intervention. What is the first recovery action?

    Correct answer: Stop braking so the wheels can roll again

    Restore rolling traction before completing the steering correction. This is not normal ABS braking advice.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 64: Skid recovery ↗

  58. After a collision, you are uninjured and able to act. What is an immediate priority?

    Correct answer: Prevent another collision at the scene

    Protect the area, request assistance, and keep emergency access clear.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 65: Accident procedures ↗

  59. You stop to help at a collision in which your truck was not involved. Where should you park?

    Correct answer: Away from the immediate scene so emergency vehicles have space

    Helping should not obstruct rescuers or create a second hazard.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 65: Accident procedures ↗

  60. Smoke indicates a vehicle fire while you are driving. Where should you stop if you can safely move off the road?

    Correct answer: In an open area away from fuel stations and combustible surroundings

    Stop safely away from things that could ignite and notify emergency services.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 66: Vehicle fires ↗

  61. Why should you avoid opening the hood fully during an engine fire?

    Correct answer: It can feed oxygen to the fire

    Shut the engine off when safe and avoid actions that intensify the fire.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 66: Engine fires ↗

  62. Smoke comes from a closed box trailer, and the cargo may be hazardous. Should you open its doors to investigate?

    Correct answer: No, keep them closed and summon emergency help

    Opening the doors can rapidly feed a cargo fire; unknown hazardous cargo adds further danger.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 66: Cargo fires ↗

  63. For a small fire you can safely tackle with the correct extinguisher and an escape path, where should you aim?

    Correct answer: At the base of the fire

    The extinguishing agent must reach the burning material rather than only the rising flames.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 66: Fire extinguishers ↗

  64. You do not know which extinguishing agent is safe for the burning cargo. What should you do?

    Correct answer: Stay clear and wait for trained firefighters

    An unsuitable agent can worsen a fire, especially when hazardous materials are involved.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 66: Fire response ↗

  65. A B:C extinguisher is intended for which hazards?

    Correct answer: Flammable-liquid and electrical fires

    Match the rating to the fire; do not assume one extinguisher covers every material.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 66: Fire extinguishers ↗

  66. What is the purpose of blocks secured snugly around cargo?

    Correct answer: Prevent the cargo from sliding

    Blocking restrains movement rather than merely filling unused cargo space.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 74: Cargo blocking ↗

  67. What does bracing between upper cargo and the compartment structure help prevent?

    Correct answer: Movement of the load

    Bracing is part of the load-restraint system, not a substitute for inspections.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 74: Cargo bracing ↗

  68. Why inspect a front-end header board before carrying a load?

    Correct answer: It helps restrain forward cargo movement toward the cab

    A sound front-end structure protects against cargo moving forward in a sudden stop.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Header boards ↗

  69. You are ordered not to open a sealed load. Which duty still remains?

    Correct answer: Check compliance with gross and axle weight limits

    A sealed-load inspection exception does not make an overweight vehicle lawful.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Sealed loads ↗

  70. What makes a dry-bulk tank load demanding in a sharp curve?

    Correct answer: A high center of gravity and possible load movement

    Reduce speed before curves and avoid abrupt maneuvers.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Dry bulk cargo ↗

  71. Why is suspended meat cargo a special concern on an off-ramp?

    Correct answer: It can swing and make a high load unstable

    The suspended load calls for conservative cornering speed.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Hanging cargo ↗

  72. How can live animals affect trailer stability?

    Correct answer: Their movement can shift the center of gravity

    Moving livestock remains a handling concern even when the load is contained.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Livestock cargo ↗

  73. Before moving an oversize or overweight load, what arrangements should you establish?

    Correct answer: Applicable permits, route and time limits, and required warning or escort equipment

    A sign alone does not authorize a special load. Determine the applicable movement conditions and equipment before departure.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Oversized loads ↗

  74. What does axle weight measure?

    Correct answer: Weight transmitted to the ground by an axle or axle group

    Axle loading is a separate limit from the vehicle’s total gross weight.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 73: Axle loading ↗

  75. Your load is within the legal maximum. Does that guarantee it is safe for bad weather or a mountain route?

    Correct answer: No, conditions can require operating below legal maximum weight

    Legal limits do not replace judgment about braking, traction, and the route.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 74: Legal weight ↗

  76. How should you determine suitable shift points for an unfamiliar commercial vehicle?

    Correct answer: Learn its specified engine-speed and road-speed ranges

    Shift patterns and useful rpm ranges vary between vehicles.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 36: Shift selection ↗

  77. Why does the handbook advise turning a retarder off on a slippery road?

    Correct answer: Its drive-wheel braking can cause a skid

    A retarder acts through the drive wheels; reduced grip can make that braking unsafe.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 37: Retarders ↗

  78. An approaching driver leaves bright lights on. What should you do?

    Correct answer: Look toward the right edge reference without staring into the glare

    Avoid adding glare or losing sight of your own lane; reduce speed when needed.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 54: Night glare ↗

  79. Why clean both sides of the windshield before a night trip?

    Correct answer: Dirt can scatter light and worsen glare

    Interior film as well as exterior dirt can obscure the road under bright lights.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 54: Night visibility ↗

  80. Your eyelids are heavy and you are struggling to stay alert. What is the safe response?

    Correct answer: Stop at a safe place and sleep

    Temporary stimulation does not replace sleep or make continued drowsy driving safe.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 54: Fatigue ↗

  81. You see dense fog ahead while approaching a safe truck stop. What is the preferable choice?

    Correct answer: Leave the roadway safely and wait for visibility to improve

    A safe off-road waiting area is preferable to entering severely limited visibility.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 55: Fog preparation ↗

  82. Why should you avoid using another vehicle’s taillights as your only guide through fog?

    Correct answer: That vehicle may be stopped off the roadway

    Identify your own road path and leave enough distance rather than blindly following lights.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 55: Fog guidance ↗

  83. When should you learn how to fit the chains carried for your drive tires?

    Correct answer: Before encountering conditions that require them

    Check fit and condition in advance so the equipment can be used correctly when required.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 55: Winter preparation ↗

  84. Which combination matters when selecting a safe descent speed?

    Correct answer: Vehicle weight, grade length and steepness, road and weather

    Different loads and grades can demand different descent speeds even under the same posted limit.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 59: Downgrade planning ↗

  85. Your truck’s brakes have failed on a downgrade and an escape ramp is available. What should you do?

    Correct answer: Use the escape ramp rather than pass it hoping to regain braking

    A designated escape ramp offers a means to stop a runaway vehicle; delay increases danger.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 62: Escape ramps ↗

  86. A hydraulic service-brake pedal goes to the floor. Which action may briefly restore hydraulic pressure?

    Correct answer: Pump the brake pedal while seeking a safe way to stop

    This is a hydraulic-pressure-loss technique, not normal ABS braking or an air-brake recovery method. Use other appropriate emergency measures and stop.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 62: Hydraulic brake failure ↗

  87. A truck tire fails, but there is no immediate collision ahead. What is the initial response?

    Correct answer: Hold the steering firmly and avoid braking until speed falls

    Control the vehicle first, then brake gently and stop safely for an inspection.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 62: Tire failure ↗

  88. Does buying a cold medicine without a prescription prove it is safe before commercial driving?

    Correct answer: No, it may cause drowsiness or impair driving

    Check warnings and appropriate medical advice; over-the-counter availability is not a safety guarantee.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 69: Medication ↗

  89. You become too ill to operate your truck safely. What should you do?

    Correct answer: Stop safely rather than continue the scheduled trip

    Illness can make continued driving unsafe even without alcohol or medication.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 69: Illness ↗

  90. Why must a commercial driver keep hazardous-material shipping papers readily accessible?

    Correct answer: Responders may need to identify the cargo when the driver cannot speak

    Accessible cargo information helps emergency personnel choose suitable precautions.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 70: Hazard recognition ↗

  91. Your vehicle was operating normally yesterday. What inspection is needed for the next trip?

    Correct answer: Inspect it before operating, including working clean lights and cargo securement

    A routine before-trip inspection can reveal new defects. Check the required vehicle components and load; yesterday’s condition is not proof of today’s safety.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 28: Before-trip inspection ↗

  92. A hot engine has a see-through coolant reservoir with level markings. How can you check the level without opening the hot system?

    Correct answer: Read the level through the reservoir wall while leaving the pressure cap closed

    A sight glass or transparent reservoir allows a visual check. Never open a hot pressurized cooling system.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 57: Coolant-level inspection ↗

  93. A breakdown forces your truck to stop on the highway shoulder. Which lights should you switch on immediately to warn approaching traffic?

    Correct answer: The four-way emergency flashers

    Flashers warn that the vehicle is stopped. They do not replace the required warning devices that must also be placed promptly.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 39: Roadside warning lights ↗

  94. In its basic steering-defect guidance, what amount of steering-wheel free play does the Texas CDL handbook warn can make steering difficult?

    Correct answer: More than 10 degrees

    This is the handbook’s inspection warning, not a universal federal out-of-service limit. Federal steering-lash limits depend on wheel size and manual or power steering under 49 CFR 393.209.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 29: Steering inspection guidance ↗

  95. A freight container is designed to transfer between a truck chassis, a train and a ship. What kind of container is it?

    Correct answer: An intermodal container

    Intermodal means the container can be used across two or more transport modes; the cargo still needs appropriate securement.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 75: Intermodal containers ↗

  96. Why should a driver not use water on burning gasoline or energized electrical equipment?

    Correct answer: It can spread burning gasoline or create an electrical-shock hazard

    Use a suitable extinguishing agent only when safe and trained to do so. Withdraw and get emergency help if the fire or material is uncertain.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 66: Water and vehicle fires ↗

  97. Before adding the separate air-brake lag factor where applicable, which three distances make up the handbook’s basic stopping-distance model?

    Correct answer: Perception, reaction and braking distances

    The vehicle moves while you recognize a hazard, while you respond and while the brakes slow it to a stop. Air brakes add a separate lag distance.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 41: Stopping-distance components ↗

  98. A newer streamlined truck climbed a hill in a relatively high gear. Should you automatically use that same gear to descend?

    Correct answer: No, the descent may require a lower gear suited to that truck and grade

    Reduced drag and different engine performance can make the old same-gear rule unsuitable. Select the correct low gear before descending.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 60: Downhill gear selection ↗

  99. Two legal parking spaces are equally suitable for your truck. One allows a forward exit; the other requires backing into traffic. Which is preferable?

    Correct answer: The space that allows you to pull forward when leaving

    Plan parking to avoid reversing when possible because you cannot see everything behind a large vehicle.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 35: Parking to avoid backing ↗

  100. Why check the rated capacity of a coupling device before assigning a load?

    Correct answer: It has limits on the weight it can pull or carry

    Section 3.2.1 identifies coupling capacity as a separate equipment rating. A load must satisfy all applicable ratings and legal limits.

    Source: Texas DL-7C, March 2026, section 2–3, PDF page 73: Gross combination weight ↗

Report a problem with this question

Question reference: tx-cdl-gk-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

States / Texas / CDL

Texas CDL: General Knowledge

100 questions on inspection, vehicle control, space, weather, emergencies and cargo safety.

All topics and study tools