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Texas CDL Texas Commercial Rules: test 1

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Texas Commercial Rules 1

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Question 1 of 20
  1. 1. Without a permit or special exception, what is the general Texas width limit for a freight truck and load, excluding authorized safety devices?
  2. 2. What is the general Texas maximum height of a freight vehicle with its load, without a permit or exception?
  3. 3. Your truck is 13 feet 10 inches high. What must you ensure under Texas law before passing structures on the route?
  4. 4. What is the ordinary Texas maximum length for a single freight motor vehicle other than a truck-tractor, with no permit or special exception?
  5. 5. In an ordinary Texas truck-tractor and semitrailer combination, how long may the semitrailer be without a permit or exception, excluding its towing device?
  6. 6. What ordinary length limit applies to each trailer or semitrailer in a Texas truck-tractor, semitrailer and trailer combination, excluding towing devices?
  7. 7. Without a special exception, what overall Texas length limit applies to an ordinary truck-and-trailer combination that is not a truck-tractor combination?
  8. 8. Without a permit or other legal exception, what are the ordinary Texas front and rear load-extension limits?
  9. 9. For an ordinary diesel freight combination with no permit or special exception, what is the Texas overall gross-weight ceiling?
  10. 10. Under the ordinary Texas rule, without a permit or exception, a single axle may not exceed what weight, including enforcement tolerances?
  11. 11. What ordinary Texas maximum applies to a tandem axle, including enforcement tolerances, with no permit or exception?
  12. 12. Which Texas agency issues oversize/overweight permits for applicable movements on Texas public roadways?
  13. 13. What information must you establish before applying for a Texas oversize/overweight permit?
  14. 14. A Texas freight trailer falls under the safety-flap rule. Its flaps must extend to within what distance of the highway surface?
  15. 15. A freight trailer has two super-single tires on its rearmost axle. Does replacing four standard tires remove the Texas safety-flap requirement?
  16. 16. Which vehicle is expressly excluded from the Texas safety-flap rule in section 547.606?
  17. 17. May a driver coast downhill on a Texas road with the transmission in neutral?
  18. 18. A truck stays in gear but the driver holds the clutch disengaged while coasting downhill. Is that allowed by Texas law?
  19. 19. Outside the statutory exception for certain structural loads, what is the maximum Texas drawbar or towing-connection distance between vehicles?
  20. 20. A vehicle tows another using a chain, rope or cable. What Texas warning flag or cloth belongs on the connection?
Review all 20 questions with answers
  1. Without a permit or special exception, what is the general Texas width limit for a freight truck and load, excluding authorized safety devices?

    Correct answer: 102 inches

    The ordinary limit is 8 feet 6 inches. Passenger-car provisions and specially authorized loads differ.

    Source: Texas Transportation Code §621.201(a) ↗

  2. What is the general Texas maximum height of a freight vehicle with its load, without a permit or exception?

    Correct answer: 14 feet

    Measure the vehicle and load together; a separate route-clearance check is still necessary.

    Source: Texas Transportation Code §621.207(a) ↗

  3. Your truck is 13 feet 10 inches high. What must you ensure under Texas law before passing structures on the route?

    Correct answer: It can pass each vertical clearance without touching

    The statute expressly places this clearance duty on operators of vehicles higher than 13 feet 6 inches.

    Source: Texas Transportation Code §621.207(b) ↗

  4. What is the ordinary Texas maximum length for a single freight motor vehicle other than a truck-tractor, with no permit or special exception?

    Correct answer: 45 feet

    Do not substitute the semitrailer or combination limit for the single-vehicle limit.

    Source: Texas Transportation Code §621.203(a) ↗

  5. In an ordinary Texas truck-tractor and semitrailer combination, how long may the semitrailer be without a permit or exception, excluding its towing device?

    Correct answer: 59 feet

    This limit applies to the semitrailer, not the entire tractor-semitrailer combination.

    Source: Texas Transportation Code §621.204(a) ↗

  6. What ordinary length limit applies to each trailer or semitrailer in a Texas truck-tractor, semitrailer and trailer combination, excluding towing devices?

    Correct answer: 28 feet 6 inches

    The twin-trailer limit is separate from the 59-foot semitrailer limit for a two-vehicle tractor combination.

    Source: Texas Transportation Code §621.204(b) ↗

  7. Without a special exception, what overall Texas length limit applies to an ordinary truck-and-trailer combination that is not a truck-tractor combination?

    Correct answer: 65 feet

    Vehicle configuration matters: do not apply this limit indiscriminately to truck-tractor combinations.

    Source: Texas Transportation Code §621.205(a) ↗

  8. Without a permit or other legal exception, what are the ordinary Texas front and rear load-extension limits?

    Correct answer: 3 feet in front and 4 feet at the rear

    Extensions are measured beyond the vehicle or combination; special loads can have additional provisions.

    Source: Texas Transportation Code §621.206(a) ↗

  9. For an ordinary diesel freight combination with no permit or special exception, what is the Texas overall gross-weight ceiling?

    Correct answer: 80,000 pounds

    Axle spacing, axle weights, tires and route limits can require a lower weight. This is not an automatic allowance for every rig.

    Source: Texas Transportation Code §621.101(b) ↗

  10. Under the ordinary Texas rule, without a permit or exception, a single axle may not exceed what weight, including enforcement tolerances?

    Correct answer: 20,000 pounds

    Compliance with the axle limit does not remove tire, gross-weight or route restrictions.

    Source: Texas Transportation Code §621.101(a)(1) ↗

  11. What ordinary Texas maximum applies to a tandem axle, including enforcement tolerances, with no permit or exception?

    Correct answer: 34,000 pounds

    This is the tandem limit; the vehicle must also meet the applicable axle-group and overall-weight rules.

    Source: Texas Transportation Code §621.101(a)(2) ↗

  12. Which Texas agency issues oversize/overweight permits for applicable movements on Texas public roadways?

    Correct answer: Texas Department of Motor Vehicles (TxDMV)

    Obtain the appropriate permit and authorized route, when applicable, before the movement.

    Source: TxDMV Oversize/Overweight Permits ↗

  13. What information must you establish before applying for a Texas oversize/overweight permit?

    Correct answer: Exact dimensions and weight of the vehicle and load

    The complete loaded measurements determine the required permit type; estimates are not an adequate substitute.

    Source: TxDMV — before applying ↗

  14. A Texas freight trailer falls under the safety-flap rule. Its flaps must extend to within what distance of the highway surface?

    Correct answer: 8 inches

    Required guards or flaps hang behind the rearmost wheels and must meet the prescribed type and mounting requirements.

    Source: Texas Transportation Code §547.606(a) ↗

  15. A freight trailer has two super-single tires on its rearmost axle. Does replacing four standard tires remove the Texas safety-flap requirement?

    Correct answer: No, two super-single tires are also covered

    The statute explicitly includes at least two super-single tires, not just four conventional tires.

    Source: Texas Transportation Code §547.606(a),(c) ↗

  16. Which vehicle is expressly excluded from the Texas safety-flap rule in section 547.606?

    Correct answer: A truck-tractor operated alone

    The section excludes a tractor operated alone and a pole trailer. Other applicable equipment rules still matter.

    Source: Texas Transportation Code §547.606(b) ↗

  17. May a driver coast downhill on a Texas road with the transmission in neutral?

    Correct answer: No

    Texas prohibits neutral coasting on a downgrade. Choose an appropriate gear before descending.

    Source: Texas Transportation Code §545.406(a) ↗

  18. A truck stays in gear but the driver holds the clutch disengaged while coasting downhill. Is that allowed by Texas law?

    Correct answer: No

    For trucks, tractors and buses, the clutch restriction applies in addition to the neutral-coasting prohibition.

    Source: Texas Transportation Code §545.406(b) ↗

  19. Outside the statutory exception for certain structural loads, what is the maximum Texas drawbar or towing-connection distance between vehicles?

    Correct answer: 15 feet

    The connection must also be strong enough to pull the weight drawn. The structural-load exception is not a general exemption.

    Source: Texas Transportation Code §545.409(a) ↗

  20. A vehicle tows another using a chain, rope or cable. What Texas warning flag or cloth belongs on the connection?

    Correct answer: White, at least 12 inches square

    This is the connection marker; it is different from the marking requirements for an overhanging load.

    Source: Texas Transportation Code §545.409(b) ↗

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Question reference: tx-cdl-rules-001

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