Idaho CDL Practice Test (ID) 2026

4.8 out of 5 (82 votes)
80% Passing score
20 Questions
4 Mistakes allowed
Embarking on the path to securing your Commercial Driver's License (CDL) in Idaho in 2026 is a significant step. To assist you in this endeavor, we present the first of our comprehensive Idaho CDL practice tests. This initial test is designed to set the foundation for your CDL journey, covering the general knowledge needed for any class of CDL, be it Class A or B, along with any endorsements you seek. Our Idaho CDL practice test consists of 20 multiple-choice questions, mirroring the format of the actual DMV test. To pass, you must correctly answer at least 16 questions. The quiz encompasses a wide range of topics crucial for every aspiring commercial driver. You'll encounter permit test questions about pre-trip vehicle inspection, basic vehicle control, gear shifting techniques, navigating hills and downgrades, effective communication with other road users, speed management, and drug and alcohol awareness. Notably, the same set of questions will be presented each time you take this CDL practice test, ensuring consistency in your practice sessions. What sets our Idaho CDL practice tests apart is their creation and review by professional driving instructors. These experts have decades of experience in training thousands of drivers. Their insights ensure that our questions are not only accurate but also relevant to what you'll face in the real CDL written knowledge test. Moreover, our Idaho CDL practice tests offer customizable practice sessions. You can focus on areas you find challenging, retake tests to improve your scores, and schedule your study sessions at your convenience. This flexibility enhances your learning experience, making it more effective and tailored to your needs. All our questions are based on the official Idaho CDL driver's manual, the same source used for the actual CDL general knowledge test. Rest assured, if it's in the manual, it's likely to be on your test. With our Idaho CDL practice test, you're not just preparing to pass in 2026; you're gearing up to excel.
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Sample Idaho CDL Test Questions - General Knowledge

Question 1

When should you select the proper lower gear for a curve?

  1. A Before entering the curve
  2. B After beginning the turn
  3. C At the curve’s midpoint
  4. D Immediately after leaving the curve

Correct answer: A – Before entering the curve

The Idaho CDL manual instructs drivers to slow to a safe speed and select the proper lower gear before entering a curve. This allows power to be applied smoothly through the turn, helping maintain vehicle stability. It also leaves the vehicle in the correct gear for accelerating after the curve.

Source: Idaho Commercial Driver’s License Manual — § 2.3.1, “Manual Transmissions—Before Entering a Curve”

Question 2

A yellow diamond warning sign displays a black truck symbol. What should you expect ahead?

This sign warns drivers to _____________.
  1. A A railroad crossing used only by freight trains
  2. B A route restricted to commercial vehicles
  3. C A mandatory truck-passing lane
  4. D Trucks entering or crossing the roadway

Correct answer: D – Trucks entering or crossing the roadway

The truck warning sign alerts drivers to a location where trucks may enter or cross the roadway. Reduce speed as conditions require and watch for large vehicles moving into or across your lane. The sign does not establish a truck-only route or designate a passing lane.

Source: Idaho Manual on Uniform Traffic Control Devices — § 2C.54, “Non-Vehicular Warning Signs (W11 Series)”

Question 3

An Idaho CDL holder is convicted of speeding while driving a personal vehicle. When must the driver notify the current employer?

  1. A Within 24 hours after conviction
  2. B Within three calendar days after conviction
  3. C Within 30 days after conviction
  4. D Only when the conviction occurred in a commercial vehicle

Correct answer: C – Within 30 days after conviction

Federal CDL regulations require a driver to notify the current employer within 30 days after a conviction for a motor-vehicle traffic-control violation other than parking. The requirement applies whether the driver was operating a commercial or personal vehicle. A citation alone is not the event that starts this deadline; the rule is based on conviction.

Source: Idaho Commercial Driver’s License Manual — § 1.4, “Other CDL Rules”, 49 CFR § 383.31(a) — Notification of Convictions for Driver Violations

Question 4

How far ahead should a commercial driver generally scan the road?

  1. A Eight to 10 seconds
  2. B 10 to 12 seconds
  3. C 12 to 15 seconds
  4. D 15 to 17 seconds

Correct answer: C – 12 to 15 seconds

A driver should generally look at least 12 to 15 seconds ahead—the distance the vehicle will travel during that time. This is about one block at lower speeds and about one-quarter mile at highway speeds. Continue shifting attention between distant conditions and hazards closer to the vehicle.

Source: Idaho Commercial Driver’s License Manual — § 2.4.1, “Seeing Ahead”

Question 5

Which three components make up total stopping distance?

  1. A Perception distance, reaction distance, and braking distance
  2. B Observation distance, response distance, and slowing distance
  3. C Perception distance, steering distance, and reaction distance
  4. D Road-condition distance, speed distance, and braking distance

Correct answer: A – Perception distance, reaction distance, and braking distance

Perception distance is traveled while the driver sees and recognizes a hazard. Reaction distance is traveled before the driver physically applies the brakes. Braking distance begins when the brakes are applied and ends when the vehicle stops; adding these three components gives total stopping distance.

Source: Idaho Commercial Driver’s License Manual — § 2.6.1, “Stopping Distance”

Question 6

Which statement about alcohol is accurate?

  1. A Coffee can quickly remove alcohol from the bloodstream
  2. B A standard serving of beer can contain about as much alcohol as a standard shot of liquor
  3. C Experienced drinkers are not affected behind the wheel
  4. D Drinking quickly reduces alcohol’s effect on driving

Correct answer: B – A standard serving of beer can contain about as much alcohol as a standard shot of liquor

A 12-ounce serving of 5% beer, a five-ounce serving of 12% wine, and a 1.5-ounce shot of 80-proof liquor contain approximately equal amounts of alcohol. Alcohol affects driving regardless of the beverage in which it is consumed. Coffee, cold showers, and fresh air do not speed the body’s fixed processing rate; only time lowers the amount present.

Source: Idaho Commercial Driver’s License Manual — § 2.22.1, “Alcohol and Driving”

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