Idaho CDL Class B Practice Test (ID) 3

4.8 out of 5 (56 votes)
80% Passing score
20 Questions
4 Mistakes allowed
Are you ready to enhance your skills for the Idaho CDL Class B license? Our third Idaho CDL practice test is here to assist you reach that goal in 2026! Featuring 20 questions, this test is a crucial tool for those aiming to excel in their Idaho Class B CDL exam. To pass, you'll need to correctly answer at least 16 questions, a challenge we know you're up to. Diving into the contents of this DMV practice test, you'll find it encompasses a broad spectrum of topics crucial for every aspiring commercial driver. From the intricacies of pre-trip vehicle inspection to mastering basic vehicle control, each question is crafted to test your knowledge and prepare you for real-world scenarios. You'll navigate through nuances of shifting gears - yes, we cover downshifting too! - and learn the best practices for handling hills and steep downgrades. But that's not all. Our Idaho CDL class B practice test also delves into essential communication strategies with other drivers and speed control techniques, ensuring you're well-rounded in every aspect of driving. What's more, our CDL practice test addresses crucial topics like drug and alcohol awareness, ensuring you're not just a skilled driver, but a responsible one too. And don't worry about seeing the same questions over and over - our practice test is dynamic, updated regularly to stay current with 2026 standards and regulations. Unlike the real DMV permit test, ours isn't timed. This means you can take all the time you need to thoroughly understand each question and its implications. It's a perfect setup for deep learning, allowing you to absorb information at your own pace. But perhaps the most beneficial feature is our immediate feedback system. Each question comes with a detailed explanation, helping you understand the reasoning behind each correct and incorrect answer. It's an interactive learning experience designed to enhance your understanding and prepare you for success. So, if you're targeting the Class B CDL in Idaho in 2026, this practice test isn't just a resource - it's your ally in achieving your goals!
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Sample Idaho CDL Test Questions - General Knowledge

Question 1

Which checks belong in the trailer-front portion of a vehicle inspection?

  1. A Verify that the header board is secure, undamaged, and strong enough to contain the cargo
  2. B Verify that an equipped canvas or tarp carrier is securely mounted
  3. C Inspect an enclosed trailer’s front for cracks, bulges, or holes
  4. D All of the above

Correct answer: D – All of the above

The trailer-front inspection includes several related checks. If equipped, the header board must be secure, free of damage, and strong enough to contain the cargo. A canvas or tarp carrier must be securely mounted and fastened, while the front of an enclosed trailer must be examined for damage such as cracks, bulges, or holes.

Source: Idaho Commercial Driver’s License Manual — § 11.4.1, “Trailer Front—Header Board”

Question 2

What must a driver do when approaching a red-and-white, downward-pointing triangular sign?

When approaching this sign _______________.
  1. A Stop in every situation before continuing
  2. B Enter the intersection before cross traffic arrives
  3. C Slow down, stop if safety requires, and yield to conflicting traffic
  4. D Continue because other traffic must yield

Correct answer: C – Slow down, stop if safety requires, and yield to conflicting traffic

In Idaho, a driver approaching a yield sign must slow to a speed reasonable for existing conditions and stop if safety requires. After slowing or stopping, the driver must yield to a vehicle already in the intersection or approaching closely enough to present an immediate hazard. The sign does not always require a complete stop.

Source: Idaho Code § 49-807(3) — Stop Signs and Yield Signs

Question 3

A qualified person other than the driver may attend a vehicle carrying Division 1.1, 1.2, or 1.3 explosives when it is on which property?

  1. A The shipper’s property
  2. B The carrier’s property
  3. C The consignee’s property
  4. D Any of the above

Correct answer: D – Any of the above

Federal attendance rules recognize the shipper’s, carrier’s, and consignee’s properties for this purpose. At any of these locations, another properly designated person may attend the vehicle. That attendant must be aware of the material’s hazards, know the required emergency actions, and be authorized and able to move the vehicle when necessary.

Source: Idaho Commercial Driver’s License Manual — § 9.6.1, “Parking with Division 1.1, 1.2, or 1.3 Explosives”, 49 CFR § 397.5 — Attendance and Surveillance of Motor Vehicles

Question 4

What is black ice?

  1. A A thin, nearly transparent layer of ice through which the pavement remains visible
  2. B A ridge of dirty ice along the roadway’s shoulder
  3. C Ice that has almost completely melted and is no longer slippery
  4. D A harmless discoloration of the pavement

Correct answer: A – A thin, nearly transparent layer of ice through which the pavement remains visible

Black ice is a thin, clear layer through which the road surface can still be seen. Because it often makes the pavement look wet rather than frozen, it can be difficult to recognize. When the temperature is below freezing and the roadway appears wet, treat the surface as potentially icy and reduce speed accordingly.

Source: Idaho Commercial Driver’s License Manual — § 2.6.2, “Matching Speed to the Road Surface—Black Ice”

Question 5

An individual article on a flatbed is seven feet long and is not blocked against forward movement. Under the general cargo-securement rule, what is the minimum number of tiedowns?

  1. A One
  2. B Two
  3. C Three
  4. D Four

Correct answer: B – Two

Federal cargo-securement rules require at least two tiedowns for an unblocked article that is longer than five feet but no longer than 10 feet, regardless of its weight. This minimum-number rule works together with requirements for adequate tiedown strength. Different rules can apply when cargo is blocked against forward movement or belongs to a commodity with special securement requirements.

Source: 49 CFR § 393.110(b)(2)(ii) — What Else Do I Have to Do to Determine the Minimum Number of Tiedowns?

Question 6

Which statement accurately describes a rear drive-wheel braking skid in a combination vehicle?

  1. A The trailer can push the towing vehicle sideways into a jackknife
  2. B Locked drive wheels have more traction than rolling wheels
  3. C This type of skid cannot cause a jackknife
  4. D Only the vehicle’s front wheels can slide sideways

Correct answer: A – The trailer can push the towing vehicle sideways into a jackknife

A rear drive-wheel braking skid occurs when the drive wheels lock. Because locked wheels usually have less traction than rolling wheels, the rear of the towing vehicle can slide sideways. In a combination vehicle, the trailer may continue pushing forward and force the towing vehicle farther sideways, producing a sudden jackknife.

Source: Idaho Commercial Driver’s License Manual — § 2.19.1, “Drive-Wheel Skids”

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