Indiana CDL Combination Test (IN) 2026

4.9 out of 5 (94 votes)
80% Passing score
20 Questions
4 Mistakes allowed
Are you ready to take on the unique challenges of driving combination vehicles in Indiana? Our Indiana combination CDL test is specifically designed to help you prepare for your Commercial Driver's License (CDL) combination vehicles endorsement. This Indiana BMV practice test covers a comprehensive range of topics essential for mastering the safe operation of combination vehicles. From coupling and uncoupling to pre-trip inspections, driving techniques, backing and maneuvering, and air brake systems, our Indiana DMV practice test ensures you have the knowledge needed to excel. This Indiana combination vehicle test consists of 20 multiple-choice questions, and you'll need to answer at least 16 correctly to pass. Each question delves into critical aspects of operating combination vehicles, such as the increased stopping distances required due to their greater weight. Understanding these nuances is crucial for maintaining safety on the road and confidently handling the unique challenges posed by larger, heavier vehicles. One of the advantages of our Indiana permit practice test is that it is not timed. You can take as much time as you need to work through each question, ensuring you fully understand each concept before moving on. This flexibility allows you to study at your own pace and solidify your knowledge without feeling rushed. Our CDL combination test is regularly updated to reflect the most current driving laws and regulations in Indiana. We ensure that you are studying the most relevant and up-to-date information, so you are fully prepared for the real test. With updates for 2026, you can trust that our Indiana BMV practice test is reliable and accurate. At the end of the practice permit test, you'll receive a detailed summary of your performance. This summary highlights the questions you answered incorrectly and provides the correct answers, allowing you to learn from your mistakes and improve your understanding. This valuable feedback helps you focus on areas that need improvement, ensuring you are well-prepared for the official CDL combination test. Prepare for your CDL combination vehicles endorsement with confidence by using our Indiana combination CDL test. With thorough coverage of essential topics, flexible study options, and up-to-date information, you'll be ready to tackle the challenges of driving combination vehicles on Indiana's roads.
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Sample Indiana Combination Test Questions

Question 1

What are the two functions of a trailer’s emergency air line?

  1. A It operates the brake lights and ABS warning lamp
  2. B It cools the brakes and supplies the suspension
  3. C It fills the trailer air tanks and controls the emergency brakes
  4. D It applies the service brakes and releases the fifth wheel

Correct answer: C – It fills the trailer air tanks and controls the emergency brakes

The Indiana CDL manual gives the emergency line two functions. It supplies air to the trailer’s air tanks and controls the trailer emergency brakes. A loss of pressure in this line causes the trailer emergency brakes to apply. Emergency lines are commonly identified by red hoses or couplers to distinguish them from blue service lines.

Source: Commercial Driver’s License Manual – Modernized Testing System — § 6.2.4, “Trailer Air-lines”

Question 2

Which procedure correctly tests the trailer emergency brakes?

  1. A Charge the system, pull out the trailer air-supply control, and gently pull against the trailer
  2. B Move forward slowly and apply only the trailer hand valve
  3. C Fan the brake pedal until the low-air warning activates
  4. D Set the tractor parking brake and increase engine speed

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

First charge the trailer air system and confirm that the trailer rolls freely. Stop and pull out the trailer air-supply control, or place it in the emergency position. Then pull gently against the trailer with the tractor. Resistance confirms that the trailer emergency brakes have applied.

Source: Commercial Driver’s License Manual – Modernized Testing System — § 6.5.2, “Combination Vehicle Brake Check”

Question 3

What is the first listed step when coupling a tractor to a semitrailer?

  1. A Connect the air and electrical lines
  2. B Inspect the fifth wheel
  3. C Back completely under the trailer
  4. D Raise the landing gear

Correct answer: B – Inspect the fifth wheel

The coupling procedure begins with an inspection of the fifth wheel. Check for damaged or missing parts, secure mounting, proper lubrication, open jaws, and the correct plate position. A sliding fifth wheel must be locked, and the kingpin must not be bent or broken. These checks occur before the tractor is backed under the trailer.

Source: Commercial Driver’s License Manual – Modernized Testing System — § 6.4.1, “Coupling Tractor-Semitrailers”

Question 4

Before backing under a semitrailer, how should its height be adjusted?

  1. A High enough for the fifth wheel to pass under the kingpin
  2. B With the kingpin several inches above the fifth wheel
  3. C With the bottom of the kingpin level with the fifth-wheel plate
  4. D Low enough for the tractor to lift the trailer slightly while backing under

Correct answer: D – Low enough for the tractor to lift the trailer slightly while backing under

Indiana’s coupling procedure calls for the trailer to be low enough that the tractor raises it slightly while backing under. This promotes proper contact between the fifth wheel and trailer apron. Adjust the landing gear if the height is incorrect. A trailer positioned too high may not couple correctly.

Source: Commercial Driver’s License Manual – Modernized Testing System — § 6.4.1, “Coupling Tractor-Semitrailers”

Question 5

How should a driver test the trailer service brakes?

  1. A Move forward slowly and apply the trailer brakes with the hand control
  2. B Accelerate rapidly and release the accelerator
  3. C Pull out the trailer air-supply control while moving
  4. D Set the tractor parking brake and turn the steering wheel

Correct answer: A – Move forward slowly and apply the trailer brakes with the hand control

With normal air pressure, release the parking brakes and move the vehicle forward slowly. Apply the trailer brakes with the hand control, if the vehicle has one. You should feel the trailer brakes engage, confirming that they are connected and operating. During normal driving, use the foot brake rather than the trailer hand control.

Source: Commercial Driver’s License Manual – Modernized Testing System — § 6.5.2, “Combination Vehicle Brake Check”

Question 6

Which component helps the trailer service brakes apply more quickly after receiving a service-line signal?

  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 control. It connects to relay valves on the trailer. The relay valves allow the trailer brakes to apply more quickly than they otherwise would. The tractor protection valve serves a different purpose by protecting the tractor’s air supply.

Source: Commercial Driver’s License Manual – Modernized Testing System — § 6.2.4, “Trailer Air-lines”

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