Washington DC CDL General Knowledge Practice Test (DC) 2

5 out of 5 (51 votes)
80% Passing score
20 Questions
4 Mistakes allowed
As a Washingtonian gearing up to acquire your CDL, you understand the importance of thorough preparation. Our second Washington DC CDL General Knowledge Practice Test is a pivotal step in that process. This test is designed with 20 CDL test questions, making it a little shorter than the actual DMV test, allowing for a shorter study session. To pass, you'll need to correctly answer at least 16 questions. This requirement ensures that you are well-prepared for the real permit test. What sets our Washington DC CDL practice test apart is its wide-ranging content. Whether you're aiming for a Class A or Class B driver's license, with any endorsements, this general knowledge test is a necessary starting point. The questions are comprehensive, covering topics from pre-trip vehicle inspection to gear shifting, including downshifting, handling hills and steep downgrades, communication strategies with other drivers, speed control, and crucial knowledge about drug and alcohol awareness. Our DC CDL general knowledge practice test is an excellent tool to get familiar with the type of questions you will face in the actual CDL written test in DC in 2026. It's formatted to resemble the real test as closely as possible, aiding in your preparation. Moreover, we regularly update our content to reflect the latest driving laws and regulations, ensuring that you are studying the most relevant and current information as of 2026. Another key aspect is the no-pressure environment of our CDL practice tests. Unlike the real DMV permit test where the stakes are high, our practice environment allows you to learn at your own pace, reducing stress and enhancing retention. You can take the test multiple times, and each time, you'll face the same set of questions, enabling effective revision and confidence-building. Prepare with our Washington DC CDL General Knowledge Practice Test, and take a significant step towards passing your DMV test with flying colors in 2026.
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Sample Washington DC CDL Test Questions - General Knowledge

Question 1

Which group consists of steering-system components?

  1. A Brake drums, slack adjusters, and pushrods
  2. B Leaf springs, U-bolts, and shock absorbers
  3. C Fifth wheel, kingpin, and apron
  4. D Steering gearbox, connecting arms, and tie rods

Correct answer: D – Steering gearbox, connecting arms, and tie rods

The steering system includes the steering gearbox and the links, arms, and rods connecting it to the wheels. These parts must be checked for looseness, wear, cracks, and missing fasteners or cotter keys. The other choices list brake, suspension, or coupling components.

Source: DC DMV Commercial Driver License Manual — § 11.2.1, “Steering”

Question 2

Which factor must be considered when deciding how much liquid to place in a cargo tank?

  1. A The shipper’s preferred delivery quantity alone
  2. B The weight of the liquid
  3. C The driver’s estimate without calculations
  4. D The exterior color of the tank

Correct answer: B – The weight of the liquid

The liquid’s weight is one factor that determines how much may be loaded. A tank filled with a dense liquid can exceed legal vehicle-weight limits. Drivers must also account for the liquid’s expansion during transportation and leave the required outage rather than filling the tank completely.

Source: DC DMV Commercial Driver License Manual — §§ 8.2.6–8.2.7, “Outage” and “How Much to Load?”

Question 3

What safety problem is a helper primarily used to address while you are backing?

  1. A Blind spots that the driver cannot see
  2. B Selecting the proper transmission gear
  3. C Keeping the passenger-side mirror available
  4. D Reducing the driver’s workload

Correct answer: A – Blind spots that the driver cannot see

A helper can watch blind spots that are not visible from the driver’s seat or mirrors. The helper should stand near the rear where the driver can see the helper and should use agreed-upon hand signals. If the driver loses sight of the helper, the vehicle should be stopped.

Source: DC DMV Commercial Driver License Manual — § 2.2.3, “Backing Safely—Use a Helper”

Question 4

During an emergency stop, how should you brake to maintain vehicle control?

  1. A Brake hard while making large steering movements
  2. B Lock the wheels and keep them locked
  3. C Keep the vehicle straight while preserving the ability to steer
  4. D Use all of these methods

Correct answer: C – Keep the vehicle straight while preserving the ability to steer

Brake in a way that keeps the vehicle traveling in a straight line while retaining the ability to steer if necessary. With controlled braking, apply the brakes as hard as possible without locking the wheels and keep steering movements small. If the wheels lock, release and reapply the brakes as soon as possible.

Source: DC DMV Commercial Driver License Manual — § 2.17.2, “How to Stop Quickly and Safely”

Question 5

What does a red octagonal STOP sign require a commercial motor vehicle driver to do?

When approaching this sign _____________.
  1. A Stop only when cross traffic is present
  2. B Yield without stopping if the roadway appears clear
  3. C Slow down and look in both directions
  4. D Make a full stop

Correct answer: D – Make a full stop

A STOP sign indicates that a full stop is always required on the controlled approach. The requirement does not depend on whether another vehicle is immediately visible. It cannot be treated as a yield sign by a commercial motor vehicle driver.

Source: Manual on Uniform Traffic Control Devices, 11th ed. — § 2B.04, “STOP Sign (R1-1) and ALL-WAY Plaque (R1-3P)”

Question 6

After the first 50-mile cargo check, which time-or-distance interval is a required reinspection trigger if no earlier duty-status change occurs?

  1. A 1 hour or 100 miles, whichever comes first
  2. B 2 hours or 200 miles, whichever comes first
  3. C 3 hours or 150 miles, whichever comes first
  4. D 4 hours or 400 miles, whichever comes first

Correct answer: C – 3 hours or 150 miles, whichever comes first

Federal regulation requires a truck or truck-tractor driver to inspect cargo within the first 50 miles and reexamine it after a duty-status change, three hours, or 150 miles, whichever occurs first. Necessary securement adjustments must be made. Limited exceptions apply when a sealed vehicle may not be opened or the loading method makes cargo inspection impracticable.

Source: DC DMV Commercial Driver License Manual — § 3.1, “Inspecting Cargo”, 49 CFR § 392.9(b)(2)–(4) – Inspection of cargo, cargo securement devices and systems

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