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Florida CDL Combination Vehicles: test 3

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Florida CDL Combination Vehicles 3

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Question 1 of 5
  1. 1. You are unsure whether the parked trailer has spring brakes. What should you do before uncoupling?
  2. 2. When uncoupling a loaded trailer, how far should you lower the landing gear after firm ground contact?
  3. 3. How should the disconnected trailer electrical cable be stored?
  4. 4. While operating the fifth-wheel release, where should your legs and feet be?
  5. 5. You have pulled the fifth-wheel clear but kept the tractor frame under the trailer. What should you verify before pulling away fully?
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  1. You are unsure whether the parked trailer has spring brakes. What should you do before uncoupling?

    Correct answer: Chock its wheels

    Stored air can leak away; use chocks when spring-brake protection is uncertain.

    Source: Florida Commercial Driver's License Manual, July 2022, section 6.4.2 Step 3 Chock Trailer Wheels, printed page 6-9 (physical PDF page 97) ↗

  2. When uncoupling a loaded trailer, how far should you lower the landing gear after firm ground contact?

    Correct answer: A few extra low-gear turns, without lifting off the fifth-wheel

    Support some weight to ease release without creating an unsafe gap or over-lifting.

    Source: Florida Commercial Driver's License Manual, July 2022, section 6.4.2 Step 4 Lower the Landing Gear, printed page 6-9 (physical PDF page 97) ↗

  3. How should the disconnected trailer electrical cable be stored?

    Correct answer: Supported, plug downward to keep moisture out

    Protect the plug from moisture and the cable from moving parts or road damage.

    Source: Florida Commercial Driver's License Manual, July 2022, section 6.4.2 Step 5 Disconnect Air-lines and Electrical Cable, printed page 6-9 (physical PDF page 97) ↗

  4. While operating the fifth-wheel release, where should your legs and feet be?

    Correct answer: Clear of the tractor’s rear wheels

    Unexpected vehicle movement can cause severe injury near the wheels.

    Source: Florida Commercial Driver's License Manual, July 2022, section 6.4.2 Step 6 Unlock Fifth Wheel, printed page 6-9 (physical PDF page 97) ↗

  5. You have pulled the fifth-wheel clear but kept the tractor frame under the trailer. What should you verify before pulling away fully?

    Correct answer: The landing gear is sound and the ground supports the trailer

    After pulling partly clear, set the tractor parking brake and select neutral. Check that the ground supports the trailer and the landing gear is undamaged before releasing the brake and pulling fully clear.

    Source: Florida Commercial Driver's License Manual, July 2022, section 6.4.2 Steps 8–10 Secure Tractor / Inspect Trailer Supports / Pull Tractor Clear, printed page 6-10 (physical PDF page 98) ↗

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Question reference: fl-cdl-combo-041

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Florida CDL Combination Vehicles: test 3

5 questions from this subject. 45 questions on tractor-trailer control, coupling, air connections and inspections.

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