Michigan CDL Combination Practice Test (MI) 2

4.9 out of 5 (53 votes)
80% Passing score
20 Questions
4 Mistakes allowed
Prepare to ace your Commercial Driver's License test with our Michigan combination CDL practice test. This second CDL combination practice test on our site offers a balanced mix of 20 multiple-choice questions, covering essential topics from the official drivers manual. You'll encounter questions about inspection procedures, safe driving practices, air brake systems, and more. To pass, you need to answer at least 16 questions correctly. Our Michigan combination vehicle test is designed to give you confidence and ensure you are thoroughly prepared for the permit test. Key areas include understanding the risks of jackknifing, where the trailer swings out of alignment with the tractor. Learning to avoid this dangerous situation through smooth braking and careful handling is crucial for safe driving. One of the unique aspects of driving in Michigan is the varied weather conditions and terrain across the state. From navigating icy roads in the Upper Peninsula to managing the busy traffic in Detroit, this DMV practice test will help you prepare for real-world driving scenarios. The questions are based on the same manual that the real DMV permit test draws from, ensuring that you're studying relevant and accurate information. Convenience is key with our Michigan practice permit test. Available online 24/7, you can take the test whenever it suits your schedule, making it easier to fit your study time around your busy life. Unlike traditional driving schools, you're not bound by specific class times. After completing the Michigan driving test practice, you can review your answers and see detailed explanations and hints for any questions you missed. This feature helps reinforce your learning and ensures you understand the material thoroughly before taking the real test. By practicing with our combination CDL test, you'll be better prepared to handle Michigan's unique driving conditions and requirements. Boost your confidence, enhance your knowledge, and get ready to pass your CDL test with flying colors.
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Sample Michigan Combination Test Questions

Question 1

Which component allows trailer brakes to apply quickly in response to pressure in the service line?

  1. A Quick-release valve
  2. B Relay valve
  3. C Front-brake limiting valve
  4. D Tractor protection valve

Correct answer: B – Relay valve

The service line carries a pressure signal controlled by the foot brake or trailer hand valve. Relay valves respond to that signal by sending the proper amount of air from the trailer tanks to the brakes. This arrangement allows the trailer brakes to apply faster than sending application air all the way from the tractor.

Source: 2024 Michigan Commercial Driver’s License Manual — § 6.2.4, “Trailer air lines”

Question 2

During an applied air-leakage test on a combination vehicle, pressure must not drop by more than how many psi in one minute?

  1. A 2 psi
  2. B 2½ psi
  3. C 3 psi
  4. D 4 psi

Correct answer: D – 4 psi

The Michigan CDL manual’s applied-leakage procedure calls for charging the system to governor cutout, shutting off the engine, releasing the parking brakes, and fully applying the foot brake. Hold the application for one minute. A combination vehicle that loses more than 4 psi has excessive leakage and must be repaired before driving.

Source: 2024 Michigan Commercial Driver’s License Manual — § 5.3.3, “Step 7 final air brake check”

Question 3

The fifth-wheel jaws have closed around the kingpin, but the locking lever is not in the locked position. What does this indicate?

  1. A The coupling is secure enough for low-speed travel
  2. B The entire fifth wheel must be replaced
  3. C The coupling is not secure and must be corrected before driving
  4. D The fifth wheel is ready to slide for weight adjustment

Correct answer: C – The coupling is not secure and must be corrected before driving

A proper fifth-wheel inspection includes checking that the jaws surround the kingpin shank, the locking lever is locked, and the safety latch is in position. A lever that has not reached the locked position indicates an improper coupling. Do not drive the coupled unit until the problem is corrected.

Source: 2024 Michigan Commercial Driver’s License Manual — § 6.4.1, “Coupling tractor-semitrailers”

Question 4

Why should cargo in a combination vehicle be kept as low as possible?

  1. A It lowers the center of gravity and reduces rollover risk
  2. B It makes every part of the load easier to unload
  3. C It guarantees lower fuel consumption
  4. D It prevents normal tire wear

Correct answer: A – It lowers the center of gravity and reduces rollover risk

The Michigan CDL manual emphasizes keeping cargo close to the ground because raising the load raises the vehicle’s center of gravity. A higher center of gravity makes a truck or trailer easier to overturn. Keeping the load low, centered, and properly distributed improves stability and reduces rollover risk.

Source: 2024 Michigan Commercial Driver’s License Manual — § 6.1.1, “Rollover risks”

Question 5

Which procedure correctly tests the trailer emergency brakes?

  1. A Open both air-line shutoff valves at the rear of the last trailer
  2. B Charge the system, pull out the trailer air-supply control, and gently pull against the trailer
  3. C Shut off the engine and repeatedly press the brake pedal
  4. D Release all parking brakes and accelerate normally

Correct answer: B – Charge the system, pull out the trailer air-supply control, and gently pull against the trailer

Charge the trailer air system and first verify that the trailer can roll freely. Stop, pull out the trailer air-supply control or place it in the emergency position, and gently pull forward with the tractor. The trailer should resist movement, showing that its emergency brakes are applied.

Source: 2024 Michigan Commercial Driver’s License Manual — § 6.5.2, “Combination vehicle brake check”

Question 6

If a trailer breaks away and separates both air lines, what should occur in addition to application of the trailer emergency brakes?

  1. A All air should drain from the tractor
  2. B The tractor protection valve should close
  3. C The tractor protection valve should open fully
  4. D The trailer air-supply valve should remain open

Correct answer: B – The tractor protection valve should close

A breakaway tears open the emergency supply line, causing the trailer emergency brakes to apply. The pressure loss also closes the tractor protection valve and causes the trailer air-supply control to pop out. Closing the valve prevents air from continuing to escape from the tractor’s brake system.

Source: 2024 Michigan Commercial Driver’s License Manual — § 6.2.4, “Trailer air lines”

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