Washington CDL Tanker Practice Test

The Washington CDL Tanker test is a multiple-choice knowledge test you take for your commercial learner's permit. Washington State Department of Licensing (DOL) says you need 80% to pass (source).

Last updated Oct 7, 2026. FirstTry CDL is a CDL permit test prep site by Hive Asset Group, LLC.

By Scott Wilder, Editor

Last reviewed against the Washington CDL manual on October 7, 2026

Scott Wilder on X | scottwilderhq.com

FirstTry CDL is a CDL permit test prep site by Hive Asset Group, LLC. It offers free exam-style practice tests built from the official CDL manual. FirstTry CDL is not affiliated with any DMV, FMCSA or government agency. Practice questions are exam-style questions built from the official CDL manual, not actual test questions.

Washington CDL permit facts

What	What Washington says	Source
Tanker pass mark	80%	Official page
Tanker test questions	20	Official page
CLP fee	$40	Official page
CLP validity	180 days. Renew once within 30 days of expiring for 180 more days. Doubles/triples and hazmat tests do not renew with the CLP	Official page
CLP holding period	Wait 14 calendar days after your original or upgraded CLP before the skills test	Official page
Test languages	The CDL knowledge test comes in English, Spanish, Russian and Serbian-Croatian. Language interpreters are not allowed. The study guide is English only.	Official page

20 question Tanker practice test

1. Tank vehicles come in many types. Where do you learn how to inspect yours?
1. A. On a road sign
2. B. From a friend at the dock
3. C. From the load's shipping paper
4. D. In the vehicle's operator manual
Show answer
Answer: D. In the vehicle's operator manual
The manual says to check the vehicle's operator manual to know how to inspect your tank vehicle.
From the official CDL manual, section 8.1 Inspecting Tank Vehicles.
2. How do you handle required equipment on your tanker?
1. A. Find out what is required, have it, and make sure it works
2. B. Carry it only if you have room
3. C. Carry it only on long trips
4. D. Wait for an officer to ask
Show answer
Answer: A. Find out what is required, have it, and make sure it works
The manual says to find out what you must carry and make sure you have it and that it works.
From the official CDL manual, section 8.1.3 Special Equipment.
3. Why must you keep tank vents clear?
1. A. So the tank looks clean
2. B. So they work correctly
3. C. So the load weighs less
4. D. So the tires stay cool
Show answer
Answer: B. So they work correctly
The manual says to keep the vents clear so they work correctly.
From the official CDL manual, section 8.1.1 Leaks.
4. What is the most important thing to check for on any tank vehicle?
1. A. Leaks
2. B. Tire tread depth
3. C. Mirror shape
4. D. Horn sound
Show answer
Answer: A. Leaks
The manual says leaks are the most important item to check on all tank vehicles.
From the official CDL manual, section 8.1.1 Leaks.
5. Which load is usually carried in an un-baffled tank?
1. A. Gasoline
2. B. Acid
3. C. Milk
4. D. Chemicals
Show answer
Answer: C. Milk
Un-baffled tanks usually carry food products such as milk.
From the official CDL manual, section 8.2.5 Un-baffled Tanks.
6. You are ready to leave. One manhole cover is still open. What should you do?
1. A. Drive slowly and close it later
2. B. Close it before you drive
3. C. Leave it open if the tank is full
4. D. Leave it open if the weather is dry
Show answer
Answer: B. Close it before you drive
The manual says never drive a tank vehicle with open valves or manhole covers.
From the official CDL manual, section 8.1.2 Check Special Purpose Equipment.
7. When should you be especially careful in a smooth bore tank?
1. A. When starting and stopping
2. B. Only on straight roads
3. C. Only when parked
4. D. Only in daylight
Show answer
Answer: A. When starting and stopping
The manual says to be extremely cautious, especially when starting and stopping.
From the official CDL manual, section 8.2.5 Un-baffled Tanks.
8. In a tank vehicle, how should you make turns and lane changes?
1. A. Quickly, to save time
2. B. Smoothly
3. C. Only at high speed
4. D. Without slowing
Show answer
Answer: B. Smoothly
The manual says to make smooth turns and lane changes.
From the official CDL manual, section 8.3.1 Drive Smoothly.
9. What should manhole covers have, and what should they do?
1. A. Locks only, and stay loose
2. B. Paint, and stay open
3. C. Gaskets, and close correctly
4. D. Springs, and open on bumps
Show answer
Answer: C. Gaskets, and close correctly
The manual says covers must have gaskets and close correctly.
From the official CDL manual, section 8.1.1 Leaks.
10. An officer finds your tank leaking. What will happen to you?
1. A. A warning only, then you drive on
2. B. You must drive to the next town
3. C. The load is just weighed
4. D. You will be cited and stopped from driving further
Show answer
Answer: D. You will be cited and stopped from driving further
The manual says you will be cited and prevented from driving further.
From the official CDL manual, section 8.1.1 Leaks.
11. What causes liquid surge?
1. A. Worn brake pads
2. B. A completely full tank
3. C. Cold weather
4. D. Movement of liquid in partially filled tanks
Show answer
Answer: D. Movement of liquid in partially filled tanks
The manual says liquid surge results from movement of the liquid in partially filled tanks.
From the official CDL manual, section 8.2.2 Danger of Surge.
12. What does a tank endorsement let a driver haul?
1. A. Only hazardous materials
2. B. Certain liquids or gases in tanks
3. C. Only dry bulk goods
4. D. Only passengers
Show answer
Answer: B. Certain liquids or gases in tanks
The manual says a tank endorsement is required for certain vehicles that transport liquids or gases.
From the official CDL manual, section 8 Tank Vehicles (introduction).
13. What kind of brake pressure helps control surge?
1. A. A steady pressure
2. B. Pumping on and off
3. C. Very light taps
4. D. Hard then soft
Show answer
Answer: A. A steady pressure
The manual says to keep a steady pressure on the brakes.
From the official CDL manual, section 8.3.2 Controlling Surge.
14. What is inside an un-baffled tank to slow the liquid?
1. A. Nothing
2. B. One baffle
3. C. Two bulkheads
4. D. A rubber lining
Show answer
Answer: A. Nothing
Un-baffled tanks have nothing inside to slow down the flow of the liquid.
From the official CDL manual, section 8.2.5 Un-baffled Tanks.
15. What is inside a baffled liquid tank?
1. A. Nothing, the tank is smooth
2. B. Solid walls with no holes
3. C. Bulkheads with holes in them
4. D. A second smaller tank
Show answer
Answer: C. Bulkheads with holes in them
Baffled tanks have bulkheads with holes that let the liquid flow through.
From the official CDL manual, section 8.2.4 Baffled Tanks.
16. Which vehicle needs the tank endorsement under the manual's rule?
1. A. A Class B truck with a 1500 gallon tank (one tank) hauling liquid
2. B. A pickup with a 20 gallon fuel can
3. C. A Class A truck with no tank
4. D. A bus with a 50 gallon water jug
Show answer
Answer: A. A Class B truck with a 1500 gallon tank (one tank) hauling liquid
A Class A or B vehicle hauling liquid in a tank over 119 gallons with 1000 gallons or more total needs the endorsement.
From the official CDL manual, section 8 Tank Vehicles (introduction).
17. You load several smaller tanks divided by bulkheads. What must you watch?
1. A. Weight distribution
2. B. Tank color
3. C. Tire brand
4. D. Cab size
Show answer
Answer: A. Weight distribution
The manual says the driver must pay attention to weight distribution.
From the official CDL manual, section 8.2.3 Bulkheads.
18. A curve sign shows 45 mph. You drive a tanker. What do tests show?
1. A. A tanker is safe at 10 mph over
2. B. A tanker is safe at the posted speed
3. C. A tanker can turn over at the posted curve speed
4. D. Only empty tankers roll
Show answer
Answer: C. A tanker can turn over at the posted curve speed
Tests have shown that tankers can turn over at the speed limits posted for curves.
From the official CDL manual, section 8.2.1 High Center of Gravity.
19. Which tank vehicle may take longer to stop?
1. A. A full one
2. B. A half full one
3. C. An empty one
4. D. They all stop in the same distance
Show answer
Answer: C. An empty one
Empty tank vehicles may take longer to stop than full ones.
From the official CDL manual, section 8.3.4 Stopping Distance.
20. When should you slow down for a curve in a tank vehicle?
1. A. After the curve
2. B. In the middle of the curve
3. C. Before the curve
4. D. Only on sharp curves
Show answer
Answer: C. Before the curve
The manual says to slow down before curves.
From the official CDL manual, section 8.3.3 Curves.

Washington CDL Tanker questions

What score do you need to pass the Washington CDL Tanker test?

Washington says you need 80% to pass the Tanker test.

Is the Washington CDL Tanker test the same as other states?

The Tanker test is built on the same federal knowledge standards in every state, so the topics match the CDL manual. Washington uses its own handbook: https://dol.wa.gov/media/pdf/42/cdlguidepdf

How much does a CDL permit cost in Washington?

CLP fee: $40.

What languages is the Washington CDL knowledge test offered in?

The CDL knowledge test comes in English, Spanish, Russian and Serbian-Croatian. Language interpreters are not allowed. The study guide is English only.

Sources

https://dol.wa.gov/driver-licenses-and-permits/commercial-driver-licenses-cdl/cdl-training-and-testing/cdl-knowledge-test
https://dol.wa.gov/driver-licenses-and-permits/commercial-driver-licenses-cdl/cdl-training-and-testing/commercial-learners-permit-clp
https://dol.wa.gov/driver-licenses-and-permits/commercial-driver-licenses-cdl/cdl-training-and-testing/cdl-skills-test
https://dol.wa.gov/media/pdf/42/cdlguidepdf
Manual sections used in this test: 8 Tank Vehicles (introduction); 8.1 Inspecting Tank Vehicles; 8.1.1 Leaks; 8.1.2 Check Special Purpose Equipment; 8.1.3 Special Equipment; 8.2.1 High Center of Gravity; 8.2.2 Danger of Surge; 8.2.3 Bulkheads; 8.2.4 Baffled Tanks; 8.2.5 Un-baffled Tanks; 8.3.1 Drive Smoothly; 8.3.2 Controlling Surge; 8.3.3 Curves; 8.3.4 Stopping Distance

Tanker practice test in nearby states