Idaho CDL General Knowledge Practice Test (ID) 2

4.7 out of 5 (66 votes)
80% Passing score
20 Questions
4 Mistakes allowed
As an Idaho resident gearing up for your CDL, our second Idaho General Knowledge Practice Test is a crucial step in your preparation in 2026. This test, featuring 20 multiple-choice questions, is designed to mirror the real CDL DMV written test, ensuring you're well-prepared, regardless of whether you're aiming for a Class A or Class B license. Our Idaho CDL practice test covers a broad range of subjects essential for every aspiring commercial driver. From pre-trip vehicle inspection and basic vehicle control to more complex topics like shifting gears, managing hills and downgrades, and understanding the nuances of road communication, this general knowledge practice test comprehensively addresses all areas. Additionally, it includes vital information on speed control and drug and alcohol awareness, crucial for safe and responsible driving. One of the unique aspects of our Idaho CDL general knowledge practice test is its non-timed nature. Unlike the actual CDL permit test, here, you can take your time to thoroughly understand and answer each question. This approach not only eases the pressure but also deepens your learning experience, allowing you to absorb information at your own pace. After completing the DMV practice test, you'll receive a detailed summary of your performance. This summary isn't just a scorecard; it highlights the questions you missed and provides the correct answers. This feedback is invaluable for your learning process, helping you identify areas that need more focus. Moreover, our platform offers customizable practice sessions. You can tailor your study sessions to concentrate on topics you find challenging. The flexibility to retake these CDL general knowledge practice tests multiple times enables you to track your progress and work towards improving your scores. And the best part? You can engage in these practice sessions at your convenience, fitting them seamlessly into your schedule. Prepare with confidence, knowing that every question you tackle on this practice test brings you one step closer to acing your Idaho DMV CDL test in 2026!
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Sample Idaho CDL Test Questions - General Knowledge

Question 1

Which statement about overhead clearance is correct?

  1. A Posted clearance measurements can always be accepted without checking
  2. B Repaving cannot reduce the space beneath an overpass
  3. C A change in cargo weight can change the vehicle’s height
  4. D A loaded van is always higher than the same van when empty

Correct answer: C – A change in cargo weight can change the vehicle’s height

The Idaho CDL manual notes that cargo weight can change a van’s height. An empty van may ride higher than the same van when loaded, so clearing an overpass while loaded does not prove it will clear when empty. Repaving or packed snow can also reduce the available clearance below a posted structure.

Source: Idaho Commercial Driver’s License Manual — § 2.7.4, “Space Overhead”

Question 2

If you are involved in a crash and are able to act, which basic steps should you take?

  1. A Protect the crash area
  2. B Notify the proper authorities
  3. C Assist injured people appropriately
  4. D All of the above

Correct answer: D – All of the above

The three basic crash-scene steps are to protect the area, notify authorities, and care for injured people. Protecting the scene helps warn approaching traffic and reduces the chance of another collision. After the area is protected, contact emergency services and provide appropriate assistance without unnecessarily moving a severely injured person.

Source: Idaho Commercial Driver’s License Manual — § 2.20, “Accident Procedures”

Question 3

How will a straight vehicle generally respond during a front-wheel skid?

  1. A The rear will immediately swing around into a spin
  2. B The vehicle will slide sideways while retaining normal steering
  3. C The vehicle will turn more sharply than the steering-wheel input
  4. D The front end will continue straight despite steering-wheel input

Correct answer: D – The front end will continue straight despite steering-wheel input

During a front-wheel skid, the front tires cannot provide the traction needed to steer. The vehicle’s front end tends to continue straight regardless of how far the steering wheel is turned. To recover, stop turning or braking so hard and allow the vehicle to slow without creating another skid.

Source: Idaho Commercial Driver’s License Manual — § 2.19.3, “Front-Wheel Skids”

Question 4

Which observation during a wheel-and-rim inspection indicates a possible defect?

  1. A Rust around the wheel nuts, which may indicate looseness
  2. B A cracked rim that has been repaired by welding
  3. C One or more missing studs that do not affect safety
  4. D Mismatched lock rings installed on the wheel

Correct answer: A – Rust around the wheel nuts, which may indicate looseness

Rust around wheel nuts can be evidence that the nuts are loose, so their tightness must be checked. Missing studs or lugs and mismatched, bent, or cracked lock rings are dangerous conditions. Wheels or rims repaired by welding are also considered unsafe. After a tire change, the wheel nuts should be rechecked after driving a short distance.

Source: Idaho Commercial Driver’s License Manual — § 2.1, “Vehicle Inspection—Wheel and Rim Problems”

Question 5

A vehicle carrying Division 1.1, 1.2, or 1.3 explosives generally may not be parked within 300 feet of which location?

  1. A A bridge, tunnel, or building
  2. B A place where people gather
  3. C An open fire
  4. D All of the above

Correct answer: D – All of the above

Federal hazardous-materials rules impose strict parking limits for vehicles carrying Division 1.1, 1.2, or 1.3 explosives. The restricted locations include bridges, tunnels, buildings, places where people work or gather, and open fires. Brief stops required by operational necessities are addressed by the applicable parking rule, but they do not eliminate the need to follow the separate fire restriction.

Source: Idaho Commercial Driver’s License Manual — § 9.6.1, “Parking with Division 1.1, 1.2, or 1.3 Explosives”, 49 CFR § 397.7 — Parking, 49 CFR § 397.11 — Fires

Question 6

What must a driver verify before transporting a sealed load that cannot be opened for inspection?

  1. A Every item inside the container is tied down
  2. B The shipper used a particular type of lock
  3. C The exact number of packages inside the container
  4. D The vehicle is within its gross and axle weight limits

Correct answer: D – The vehicle is within its gross and axle weight limits

A driver ordinarily cannot inspect the contents or internal securement of a sealed load. The driver should still verify that the vehicle does not exceed applicable gross-weight or axle-weight limits. The seal does not make an overloaded vehicle acceptable, and the driver remains responsible for checking conditions that can be determined without opening the load.

Source: Idaho Commercial Driver’s License Manual — § 3.3.5, “Sealed and Containerized Loads”

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