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Texas CDL general knowledge: test 5

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Texas CDL General Knowledge 5

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Question 1 of 20
  1. 1. What can rust around a commercial vehicle’s wheel nuts indicate?
  2. 2. When should a commercial driver select the proper low gear for a downgrade?
  3. 3. Why might an empty cargo van require more overhead clearance than the same van when loaded?
  4. 4. What does a single vehicle’s gross vehicle weight rating (GVWR) represent?
  5. 5. Why should a driver check cargo covers in the mirrors while traveling?
  6. 6. You are approaching a curve in a commercial vehicle with a manual transmission. When should you reduce speed and select the appropriate lower gear?
  7. 7. Before departure, why should you secure loose tools and other articles in the cab?
  8. 8. At dusk in rain, are identification and clearance lights alone sufficient to make your truck visible?
  9. 9. Snow covers the truck’s mirrors and side windows before departure. What is required for a safe start?
  10. 10. When is it safe to open the pressurized radiator system for a coolant check?
  11. 11. Why is listening for a horn alone an unsafe crossing check?
  12. 12. Smoke indicates a vehicle fire while you are driving. Where should you stop if you can safely move off the road?
  13. 13. A B:C extinguisher is intended for which hazards?
  14. 14. What makes a dry-bulk tank load demanding in a sharp curve?
  15. 15. Your load is within the legal maximum. Does that guarantee it is safe for bad weather or a mountain route?
  16. 16. Your eyelids are heavy and you are struggling to stay alert. What is the safe response?
  17. 17. Your truck’s brakes have failed on a downgrade and an escape ramp is available. What should you do?
  18. 18. Why must a commercial driver keep hazardous-material shipping papers readily accessible?
  19. 19. A freight container is designed to transfer between a truck chassis, a train and a ship. What kind of container is it?
  20. 20. Why check the rated capacity of a coupling device before assigning a load?
Review all 20 questions with answers
  1. 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 ↗

  2. 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 ↗

  3. 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 ↗

  4. 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 ↗

  5. 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 ↗

  6. 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 ↗

  7. 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 ↗

  8. 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 ↗

  9. 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 ↗

  10. 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 ↗

  11. 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 ↗

  12. 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 ↗

  13. 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 ↗

  14. 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 ↗

  15. 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 ↗

  16. 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 ↗

  17. 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 ↗

  18. 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 ↗

  19. 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 ↗

  20. 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 ↗

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Question reference: tx-cdl-gk-005

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