Air Brakes #1
Air Brakes Endorsement Test | Illinois 2026 #1 Page 3 of 4
Train for FREE online with our Illinois CDL air brake 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 IL Class A/Class B driver 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 the requirements for CDL may vary from state to state.
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13 . How is the parking brake released?
By tapping the accelerator twice
In vehicles with air brakes, the parking brake is controlled by a knob. The knob is pulled out to apply the brakes, and pushed in to release them.
14 . Which type of brakes do most heavy-duty vehicles have?
Gravity brakes
For safety, most heavy-duty vehicles are equipped with dual air brake systems.
15 . Vehicles with dual air brake systems:
Maintain air pressure when shut off for periods of less than four hours.
Before driving a vehicle with a dual air brake system, allow time for the air compressor to build up pressure of at least 100 psi in both the primary and secondary systems.
16 . In a dual air brake system:
One system is the main braking system and a second system is ready to be used if the first one fails.
A dual air brake system is made up of two separate air brake systems. The systems share a single set of brake controls, but each has its own air tanks, hoses, and lines.
17 . What does the air compressor governor do?
Controls the temperature of the air leaving the air storage tanks.
In an air brake system, the air compressor governor controls when the air compressor pumps air into the air storage tanks.
18 . The safety valve located on the first tank opens:
After every stop.
In an air brake system, the first tank that receives compressed air has a safety valve that releases air if the pressure gets too high. It is usually set to open at 150 psi. If the valve must open, there is a fault in the system that should be repaired by a mechanic.
2026 Illinois | Frequently Asked Questions
To acquire a CDL Tank endorsement in Illinois, you must first have a Commercial Driver's License (CDL). Next, study the Tank Vehicles section of the Illinois Commercial Driver's License Study Guide. Once prepared, schedule and pass the written tank vehicle endorsement test at a Secretary of State Driver Services facility. The endorsement will then be added to your CDL.
To obtain a CDL Tank license, it is essential to have a Commercial Driver's License (CDL) first. Then, you need to study the Tank Vehicles section of the Illinois Commercial Driver's License Study Guide. After studying, you must pass the written tank vehicle endorsement test at a Secretary of State Driver Services facility in Illinois.
While specific training or experience isn't legally mandatory for a CDL Tank endorsement in Illinois, it is highly recommended. Understanding the operation of tank vehicles and handling of liquid cargo is crucial. Studying the Tank Vehicles section of the Illinois Commercial Driver's License Study Guide and passing the written test at a Secretary of State Driver Services facility is required.
Yes, to obtain a CDL Tank endorsement in Illinois, you must pass an additional written test. This test covers specific knowledge related to the safe transport of liquid and gaseous materials in tank vehicles. The information for the test can be found in the Tank Vehicles section of the Illinois Commercial Driver's License Study Guide.
The written test for the CDL Tank endorsement in Illinois covers various subjects including: high and low center of gravity and its impact on vehicle stability, how to inspect tank vehicles, how to drive vehicles loaded with liquids or gases, and special safety considerations for hazardous materials. All these subjects are detailed in the Illinois Commercial Driver's License Study Guide.
The CDL Tank endorsement assessment evaluates your understanding of tank-specific operations. You'll be tested on handling liquid surge, inspecting tank vehicles, managing a high center of gravity, and the implications of carrying a full or partial load. However, it's primarily a knowledge test, so specific driving maneuvers aren't typically assessed in this endorsement.
Yes, drivers with a CDL Tank endorsement must comply with specific requirements and regulations. These include maintaining a clean driving record, undergoing regular medical examinations, and adhering to hours-of-service regulations. Additionally, drivers must follow safety procedures when loading and unloading tanks, and comply with hazardous materials transportation regulations if applicable.
No, you cannot legally transport liquid or gas materials without a valid CDL Tank endorsement in Illinois. This endorsement is necessary for operating a commercial vehicle designed to transport any liquid or gaseous materials within a tank or tanks having an individual rated capacity of more than 119 gallons and an aggregate rated capacity of 1,000 gallons or more.
Yes, the CDL Tank endorsement can be added to your current license in Illinois. You don't need to apply for a fresh license. However, you must pass the Tank Vehicle endorsement test. Once passed, the endorsement will be added to your existing CDL, allowing you to legally operate tank vehicles.
Yes, handling hazardous materials with a CDL Tank endorsement requires adherence to specific regulations. Drivers must pass the Hazardous Materials (HazMat) endorsement knowledge test, undergo a federal background check, and submit fingerprints. They must also follow safety protocols for loading and unloading hazardous materials, and comply with shipping paper requirements.