Combination #1
Combination Vehicles Practice Test | Washington 2026 #1 Page 3 of 3
Train for FREE online with our Washington CDL combination vehicle test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a WA combination license in 2026, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that DMV requirements for issuing a combination license may vary from state to state.
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15 . In a vehicle equipped with an automatic tractor protection valve, the valve will pop out when air pressure drops to a level between:
In vehicles equipped with an automatic tractor protection valve, the valve will pop out if air pressure drops to a level between 20 and 45 psi. When the valve pops out, the protection valve will close, stopping the flow of air.
16 . After completing a pre-trip inspection, you should ensure that the:
Before a trip, you should ensure that air reaches all air brakes on all trailers by opening up the rear emergency line and service line shut-off valves and listening for escaping air. Close both shut-off valves before beginning to drive.
17 . In a double or triple combination, the ____ trailer should be directly behind the cab.
When positioning trailers in a combination, the most heavily-loaded trailer should be the closest to the tractor. The lightest trailer should be positioned in the rear.
18 . A trailer that is too high:
Before coupling together a tractor and a trailer, you should make sure the trailer is at the proper height. If the trailer is too low, the trailer nose may be damaged. If the trailer is too high, it may not be able to couple correctly.
19 . If the emergency air line loses pressure:
The tractor protection valve keeps air in the trailer's braking system should the trailer break away or develop a leak. A loss of air pressure in the emergency line will cause the tractor protection valve to open and the emergency trailer brakes to activate.
20 . The best way to recognize that your trailer has started to skid is by:
The easiest way to become aware that your trailer has begun to jackknife is to observe it in your mirrors. Checking your trailer in your mirrors will also allow you to spot any skidding at the earliest possible moment.
2026 Washington | Frequently Asked Questions
To obtain a CDL Tank endorsement in Washington, you first need a Commercial Driver's License (CDL). Then, study the "Transporting Cargo Safely" section of the Washington CDL manual. After studying, take the written tank vehicle test at a Department of Licensing office. If you pass, the tank endorsement will be added to your CDL.
To obtain a CDL Tank license, you first need a basic Commercial Driver's License (CDL). You then need to study the relevant sections of your state's CDL manual, focusing on transporting cargo safely. After studying, you must pass a written tank vehicle test at your local Department of Licensing office. Once passed, the tank endorsement is added to your CDL.
While specific training or experience isn't legally required to obtain a CDL Tank endorsement in Washington, it's advisable to study the "Transporting Cargo Safely" section of the CDL manual thoroughly. Experience driving similar vehicles can also be beneficial. Ultimately, you must pass a written tank vehicle test at a Department of Licensing office.
Yes, an additional written knowledge test is required for the CDL Tank endorsement. The test focuses on the specific knowledge needed to safely operate tank vehicles. This includes understanding the vehicle's handling characteristics, inspecting tank vehicles, and recognizing hazards. Studying the Commercial Driver Guide provided by the Washington State Department of Licensing will help prepare for this test.
The written test for the CDL Tank endorsement covers various topics related to safely transporting liquids and gases. Subjects include understanding bulk tank loading, unloading, and inspecting procedures, recognizing the dangers of surge, handling high center of gravity, and knowing how to control internal tank pressure among others. It's crucial to study these areas thoroughly.
The CDL Tank endorsement assessment primarily focuses on knowledge rather than specific maneuvers. You'll be tested on understanding of safe loading and unloading procedures, handling of surge, control of internal tank pressure, and awareness of high center gravity risks. Practical driving skills are typically assessed during the general CDL skills test rather than the tank endorsement test.
Drivers with a CDL Tank endorsement must adhere to specific regulations and safety guidelines when transporting liquids or gases. They must understand the unique risks associated with this type of cargo, such as surge and high center of gravity. However, they are not restricted from driving other types of commercial vehicles unless there are additional endorsements or restrictions on their license.
No, a valid CDL Tank endorsement is required to transport liquid or gas materials in the United States. This endorsement ensures the driver has the necessary knowledge and skills to handle such materials safely. Driving without the proper endorsement can result in legal penalties, including fines and suspension of driving privileges.
The CDL Tank endorsement can be added to your current CDL. You don't need a fresh application for a new license. However, you will need to pass a knowledge test related to tank vehicle operation. Once you pass the test, the endorsement will be added to your existing CDL.
Yes, to handle hazardous materials with a CDL Tank endorsement, drivers must also have a Hazardous Materials (HazMat) endorsement. They must pass a written test regarding the safe transportation of hazardous goods and undergo a federal background check. Understanding safety protocols, emergency procedures, and federal regulations is crucial for handling these materials.