Washington Tanker Endorsement Test (WA) 2026

4.7 out of 5 (123 votes)
80% Passing score
20 Questions
4 Mistakes allowed
If you're gearing up for the WA CDL tanker endorsement test, this Washington state CDL practice test is an essential step in your preparation. With a strong focus on the specifics of driving tanker vehicles, the CDL tanker practice test is designed to mirror the actual Washington driving test practice you'll face at the DOL. By covering crucial topics like liquid surge, weight distribution, emergency protocols, and regulatory compliance, this WA practice written driving test equips you with the knowledge you need to handle the unique challenges that come with transporting liquids. The Washington state tanker endorsement test consists of 20 carefully selected questions that replicate the format and content of the real test. Each question is presented in a multiple-choice format, requiring you to select the most accurate answer based on your understanding of the material. To pass this knowledge test practice, you'll need to correctly answer at least 16 out of 20 questions. This passing score is aligned with the standards set by the Washington DMV, ensuring that you are fully prepared when it comes time to take the official test. One of the critical aspects of this WA CDL tanker endorsement test is its emphasis on managing the liquid surge effect, a phenomenon that can significantly impact your vehicle's stability and handling. By mastering the concepts related to liquid surge, you'll be better equipped to safely operate a tanker vehicle under various conditions. Additionally, the CDL tanker test highlights the importance of conducting regular inspections specific to tanker vehicles. These inspections are vital for ensuring the tank and vehicle components are in optimal condition, helping you avoid potential hazards on the road. What sets this Washington state permit practice test apart is its flexibility. You can retake the Washington practice written driving test as many times as necessary, allowing you to build confidence and proficiency before moving on to the next CDL practice test. Pair this DOL practice test with additional study materials like the WA driver's handbook, flashcards, and state-certified driver's education courses for a comprehensive preparation experience.
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Sample Washington Tanker Test Questions

Question 1

In tank-vehicle operation, what does the term "outage" mean?

  1. A The procedure for unloading a cargo tank
  2. B The unfilled space left for liquid expansion
  3. C The tank's total rated capacity
  4. D The compartment containing the baffles

Correct answer: B – The unfilled space left for liquid expansion

Outage is the space left in a cargo tank so the liquid can expand as it warms. A cargo tank should not be filled completely with liquid. Because different liquids expand by different amounts, the driver must know the appropriate outage requirement for the particular bulk liquid being transported.

Source: Washington State Commercial Driver Guide — § 8.2.6, “Outage”.

Question 2

When using controlled braking, how firmly should you apply the brakes?

  1. A Only lightly enough to avoid steering corrections
  2. B As hard as possible without locking the wheels
  3. C Only after reducing speed with the accelerator
  4. D Fully until the wheels lock, then release them

Correct answer: B – As hard as possible without locking the wheels

Controlled braking requires applying the brakes as hard as possible without locking the wheels. Steering movements should remain very small. If the wheels lock or a larger steering adjustment becomes necessary, release the brakes and reapply them as soon as possible after control is restored.

Source: Washington State Commercial Driver Guide — § 2.17.2, “How to Stop Quickly and Safely”—“Controlled Braking”.

Question 3

Which tank design produces the strongest forward-and-back liquid surge?

  1. A A smooth-bore tank
  2. B A tank divided by solid bulkheads
  3. C A baffled tank
  4. D All tank designs produce equal surge

Correct answer: A – A smooth-bore tank

A smooth-bore, or unbaffled, tank has nothing inside to slow the liquid's movement. This makes forward-and-back surge especially strong during starts and stops. Baffles reduce forward-and-back movement by allowing liquid to flow through holes, although they do not prevent side-to-side surge.

Source: Washington State Commercial Driver Guide — § 8.2.4, “Baffled Tanks”; § 8.2.5, “Un-baffled Tanks”.

Question 4

During a hard stop, how does liquid typically move in a partially filled tank?

  1. A It moves forward and remains against the front of the tank
  2. B It moves only toward the rear
  3. C It surges forward and then back
  4. D It remains stationary because the tank is mostly full

Correct answer: C – It surges forward and then back

During a stop, liquid in a partially filled tank surges back and forth. When a wave reaches an end of the tank, it tends to push the vehicle in the direction the wave is moving. This repeated movement can affect handling and may even move a stopped tanker on a slippery surface.

Source: Washington State Commercial Driver Guide — § 8.2.2, “Danger of Surge”.

Question 5

When loading the compartments of a tank divided by bulkheads, how should the weight be arranged?

  1. A With most of the weight in the rear compartments
  2. B Without excessive weight at either the front or rear
  3. C With most of the weight in the front compartments
  4. D With all weight concentrated in the center compartment

Correct answer: B – Without excessive weight at either the front or rear

Bulkheads divide some tanks into several smaller compartments. When loading or unloading those compartments, the driver must pay close attention to weight distribution. The load should not place too much weight at either the front or rear of the vehicle, because poor weight balance can make handling unsafe.

Source: Washington State Commercial Driver Guide — § 8.2.3, “Bulkheads”; § 3.2.4, “Balance the Weight”.

Question 6

Why might a cargo tank be only partially filled with a dense liquid?

  1. A To eliminate all liquid surge
  2. B To improve fuel mileage
  3. C To remain within legal weight limits
  4. D To avoid leaving outage

Correct answer: C – To remain within legal weight limits

Washington’s commercial driver guide explains that a full tank of dense liquid may exceed legal weight limits. For that reason, tanks carrying heavy liquids are often only partially filled. The permitted amount depends on the liquid's weight, its expected expansion during transit, and the applicable legal weight limits; partial filling does not eliminate surge.

Source: Washington State Commercial Driver Guide — § 8.2.7, “How Much to Load?”.

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