Delaware CDL Combination Practice Test (DE) 2

4.9 out of 5 (47 votes)
80% Passing score
20 Questions
4 Mistakes allowed
Preparing for your Commercial Driver's License (CDL) in Delaware has never been more efficient with our Delaware CDL combination practice test. This comprehensive test, consisting of 20 multiple-choice questions, is designed to cover critical topics such as inspection procedures, safe driving practices, and air brake systems. To pass, you'll need to correctly answer at least 16 of these questions. This DMV test practice ensures you are well-prepared for the actual permit test by focusing on real-world scenarios you will encounter on the road. One of the unique features of our Delaware driving test practice is its alignment with the format of the actual DMV test. By practicing with multiple-choice and true-or-false questions, you will develop the essential skill of eliminating incorrect answers to identify the correct one. This method not only enhances your test-taking abilities but also boosts your confidence as you become familiar with the test structure. Our Delaware CDL combination practice test is regularly updated to reflect the most current driving laws and regulations, ensuring you are studying the most relevant information. With updates for 2026, you can trust that you are learning about the latest rules of the road. Delaware presents unique driving conditions that every CDL driver should be prepared for. Whether you're navigating the busy streets of Wilmington, dealing with the coastal winds near Rehoboth Beach, or managing the rural roads in Sussex County, our combination CDL test covers it all. Understanding how to handle the risks of jackknifing, where the trailer swings out of alignment with the tractor, is crucial. This Delaware practice permit test includes questions that teach you how to avoid this dangerous situation through smooth braking and careful handling, ensuring safer driving experiences. To maximize your preparation, supplement the combination CDL practice test with additional study materials such as the Delaware driver's handbook, a state-certified driver's education course, flashcards, and road sign charts. These resources help you target all areas of the DMV permit test, ensuring a well-rounded approach to your CDL test preparation.
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Sample Delaware Combination Test Questions

Question 1

Why should the trailer hand valve not be used for routine braking while driving?

  1. A It applies the tractor brakes too strongly
  2. B It immediately releases the trailer air supply
  3. C It cannot operate the trailer brakes
  4. D Applying only the trailer brakes can cause the trailer to skid

Correct answer: D – Applying only the trailer brakes can cause the trailer to skid

The trailer hand valve should be used to test the trailer brakes, not for normal braking while driving. Because it applies the trailer brakes separately, it can cause the trailer wheels to skid. The foot brake applies the brakes throughout the combination and presents less danger of a skid or jackknife.

Source: Delaware Commercial Driver’s Manual — § 6.2.1, “Trailer Hand Valve”

Question 2

During the coupling inspection, should you look into the back of the fifth wheel to verify that the jaws surround the kingpin shank?

  1. A TRUE
  2. B FALSE

Correct answer: A – TRUE

The statement is true. During the visual inspection, look into the back of the fifth wheel and confirm that its jaws have closed around the shank of the kingpin. Also verify that there is no gap between the upper and lower fifth wheel, the locking lever is locked, and the safety latch is properly positioned.

Source: Delaware Commercial Driver’s Manual — § 6.4.1, “Coupling Tractor-Semitrailers,” Step 13, “Inspect Coupling”

Question 3

Before driving a coupled tractor-semitrailer, where should the landing gear be positioned?

  1. A One-third raised with the crank secured
  2. B Halfway raised with the crank secured
  3. C Raised only until it clears the pavement
  4. D Fully raised with the crank secured

Correct answer: D – Fully raised with the crank secured

The Delaware CDL manual requires the landing gear to be raised all the way before driving, with the crank handle secured safely. Landing gear left partly down may strike railroad tracks, pavement, or other obstacles. The driver should also verify adequate clearance between the landing gear and tractor frame for sharp turns.

Source: Delaware Commercial Driver’s Manual — § 6.4.1, “Coupling Tractor-Semitrailers,” Step 15, “Raise Front Trailer Supports (Landing Gear)”

Question 4

What should you do if the trailer is too high for proper fifth-wheel coupling?

  1. A Raise the trailer farther
  2. B Back underneath it at a higher speed
  3. C Tilt the fifth-wheel plate upward
  4. D Lower the trailer to the proper coupling height

Correct answer: D – Lower the trailer to the proper coupling height

Lower the trailer until it will be lifted slightly by the tractor as the tractor backs underneath. A trailer that remains too high may not couple correctly because the kingpin may fail to enter and lock into the fifth wheel. Recheck the alignment of the kingpin and fifth wheel before continuing.

Source: Delaware Commercial Driver’s Manual — § 6.4.1, “Coupling Tractor-Semitrailers,” Step 6, “Check Trailer Height”

Question 5

Which of these are acceptable ways to protect disconnected air lines and the electrical cable after uncoupling?

  1. A Hang the electrical cable with its plug facing down
  2. B Attach the glad hands to dummy couplers
  3. C Lock the glad hands together if the couplings permit it
  4. D All of the above

Correct answer: D – All of the above

All three methods are acceptable. The glad hands may be attached to dummy couplers or, when their design permits, coupled together to keep dirt and water out. Hang the electrical cable with its plug facing down to reduce moisture entry, and support all lines so they cannot be damaged while the tractor is driven.

Source: Delaware Commercial Driver’s Manual — § 6.4.2, “Uncoupling Tractor-Semitrailers,” Step 5, “Disconnect Air-lines and Electrical Cable”

Question 6

On trailers designed to tow another trailer, where are the service- and supply-line shutoff valves located?

  1. A Inside the tractor cab
  2. B At the rear of the tractor
  3. C At the front of the trailer
  4. D At the rear of the trailer

Correct answer: D – At the rear of the trailer

Shutoff valves, also called cut-out cocks, are installed in the service and supply air lines at the rear of trailers used to tow other trailers. In a connected set, the valves must generally remain open so air reaches the following units. The valves at the rear of the last trailer must be closed.

Source: Delaware Commercial Driver’s Manual — § 6.2.7, “Shut-off Valves”

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