How to Pass Your Washington State CDL Exam: Practice Questions and Study Guides
May 9, 2025
If you're starting your journey toward a Commercial Driver’s License (CDL) in Washington State, you probably have a lot of questions:
What should I study? What’s actually on the test? Where can I find the best resources?
Good news—you’re not alone. And even better, Washington has some excellent study tools available for free that can make your CDL schooling and testing a lot easier if you know how to use them.
As Washington state’s premier CDL School, you can trust us when we say that the following two resources are must-haves for your CDL success:
We’ll go over what these resources are, how they can help you pass the CDL exam, show you sample questions based directly on these guides, and answer common student questions that we get every day. By the end of this article, you’ll have everything you need to start getting familiar with the CDL exam.
The Best CDL Study Guides
1. Washington State Commercial Driver Guide
This guide is published by the Washington State Department of Licensing (DOL) and contains everything you need to know to pass your CDL knowledge and skills tests.
It covers topics like:
- Vehicle inspection procedures
- Driving safety
- Cargo transport regulations
- Special endorsements (hazmat, passenger, tanker, etc.)
- Washington-specific rules and testing procedures
Why It’s Helpful:
The Washington CDL exam is based directly on the topics in this guide. Study this carefully and you’ll know exactly what the examiners expect.
2. Washington State Commercial Driver License Manual
This is an updated supplement to the main guide. It includes important updates and clarifications, especially for the:
- Air brake procedures
- New federal Entry-Level Driver Training (ELDT) requirements
- Hazardous materials endorsements
Why It’s Helpful:
Rules and tests change. This updated manual has the current information you’ll be taught through a CDL School.
Washington State CDL Test: Sample Questions
Here are some sample questions based on the topics covered in the Washington State CDL Guide and Driver’s Manual that are similar to what you’ll face during your CDL exams.
You can find the answers to these questions at the end of the article. Test yourself and see where you stand!
Pre-Trip Inspection
Question: What should you check when inspecting the brake system during a pre-trip inspection?
(A) The brake linings are dry and not dangerously thin
(B) The brake drums have grease on them
(C) The brake pads are cracked
(D) Both A and C
General CDL Knowledge
Question: What is the minimum tread depth for front tires on a commercial vehicle?
(A) 1/16 inch
(B) 2/32 inch
(C) 4/32 inch
(D) 6/32 inch
Air Brakes
Question: What happens if your air pressure drops below the safety level in an air brake system?
(A) Nothing happens
(B) The brakes release automatically
(C) The emergency brakes will activate
(D) The engine shuts off
Cargo Securement
Question: What is the main reason for securing cargo properly?
(A) To improve fuel efficiency
(B) To prevent cargo from shifting and causing a crash
(C) To make the load heavier
(D) To save time during unloading
Combination Vehicles
Question: When coupling a tractor to a trailer, what should you do before backing under the trailer?
(A) Fully open the trailer’s service brake valve
(B) Lower the landing gear all the way
(C) Make sure the trailer brakes are locked
(D) Drive quickly to engage the kingpin
These sample questions show the type of real-world knowledge you’ll need—not just to pass your test, but to stay safe on the road.
FAQs About the Washington State CDL Test
Do I have to memorize the entire CDL Guide?
Not word-for-word—but you must fully understand all of the concepts.
At New Sound CDL, we break down the guide into simple, memorable parts to help you retain the important stuff.
How many questions are on the Washington State CDL knowledge test?
- General Knowledge Test: Around 50 questions
- Air Brakes Endorsement Test: About 25 questions
- Combination Vehicles Test: About 20 questions
You need to answer at least 80% of the questions correctly to pass each section.
Is the Pre-Trip Inspection test hard?
It can be tricky if you try to "cram" at the last minute.
At New Sound CDL, we teach the pre-trip inspection with hands-on practice so it becomes second nature by test day. We let you take all the time you need to ask questions and repeat the process until you’re confident.
Will the DOT examiner ask me random questions during my skills test?
Not random. Every question will be based on the official CDL Guide or Manual. Nothing will be unfair or unexpected.
Are the Washington CDL tests different from other states?
Yes, a little bit.
While the basics are the same nationwide, Washington has some state-specific rules for testing and documentation (which we teach you at New Sound).
CDL Sample Questions Answer Sheet
Pre-Trip Inspection
Question: What should you check when inspecting the brake system during a pre-trip inspection?
Answer:
(A) The brake linings should be dry, not greasy, and not dangerously thin.
General CDL Knowledge
Question: What is the minimum tread depth for front tires on a commercial vehicle?
Answer:
(C) 4/32 inch (For front tires. For other tires, it’s 2/32 inch.)
Air Brakes
Question: What happens if your air pressure drops below the safety level in an air brake system?
Answer:
(C) The emergency brakes will activate when air pressure drops too low.
Cargo Securement
Question: What is the main reason for securing cargo properly?
Answer:
(B) Cargo shifts can cause accidents, rollovers, and loss of control. Proper securement is critical for safety.
Combination Vehicles
Question: When coupling a tractor to a trailer, what should you do before backing under the trailer?
Answer:
(C) You must make sure the trailer brakes are locked.
Why is New Sound CDL School the Best In Washington?
Highest CDL Pass Rates:
80% of our students pass the CDL exam on their first try. That’s the highest rate in Washington!
Expert CDL Instructors:
All our instructors are Washington State Certified and have real trucking experience. They know what it takes to pass—and to succeed on the job.
Multilingual Classroom Support:
Our instructors and staff also speak Spanish, Russian, and Ukrainian. You’ll have the support you need in the language you feel most confident.
Modern Trucks and Equipment:
Train on clean, well-maintained automatic and manual trucks in a paved, private lot that’s on-location.
Evening CDL Classes Available:
We offer flexible schedule options for working students and parents. Nothing needs to stop you from getting your CDL.
CDL Job Placement Assistance:
We have strong partnerships with companies like Swift, McLane, and Sysco to help you find a job fast after graduation.
Supportive, Five-Star Atmosphere:
You’ll feel welcomed, respected, and encouraged from your first day with us.
Ready to Get Your Washington State CDL?
Your CDL journey starts with the right information—and the right team behind you.
With the Washington State CDL Guides, focused training, and expert coaching at New Sound CDL School, you’ll be on the road to a high-paying, stable career faster than you think.
Contact us today to learn more, schedule a tour, or enroll in the perfect CDL training program for you. We’re proud to serve students from Fife, Tacoma, Seattle, and all across Washington State!