Air Brakes #1
Air Brakes Endorsement Test | Idaho 2026 #1 Page 4 of 4
Train for FREE online with our Idaho 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 ID 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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19 . What is removed when an air tank is drained?
In an air brake system, air tanks have drains to remove accumulations of water and compressor oil. Allowing water and oil to accumulate in the system could cause damage to the brakes.
20 . Brakes out of adjustment will:
Brakes out of adjustment will fade before those that are properly adjusted. Brake adjustment must be checked frequently to help prevent brake issues.
21 . Lights that indicate that anti-lock brakes are not working are:
Vehicles equipped with Anti-Lock Braking Systems (ABS) have yellow malfunction lights to indicate issues in the braking system.
22 . If the spring brakes are on, you should:
Do not use the brake pedal when the spring brakes are on. This could damage the brakes by subjecting them to the combined forces of springs and air pressure.
23 . A low air pressure warning signal should activate:
In an air brake system, a low air pressure warning signal must come on if air pressure in the tanks falls below 60 psi. This warning signal may come in the form of a light, a buzzer, or a wig wag.
24 . When parked on a flat surface, you should:
When parking on a level surface, you should use wheel chocks. If the vehicle is not equipped with spring brakes, this is essential to prevent the trailer from moving.
25 . If the safety relief valve in an air brake system is releasing air:
The safety relief valve in an air brake system releases air if necessary to prevent pressure in the system from becoming too high. If the valve starts releasing air, there is something wrong. Have a mechanic fix the problem.
2026 Idaho | Frequently Asked Questions
To secure a CDL Doubles/Triples endorsement in Idaho, you need to have a valid commercial driver's license (CDL). You will then need to pass the Doubles/Triples Knowledge Test offered by the Idaho Transportation Department. It's also recommended to practice with a qualified trainer before the test to ensure you understand how to safely operate these types of vehicles.
To obtain a CDL Doubles/Triples license, you must already hold a Commercial Driver's License (CDL). You'll need to pass the Doubles/Triples Knowledge Test, which covers coupling and uncoupling, inspecting doubles and triples, and checking air brakes. It's also recommended to have some hands-on training with a qualified instructor to ensure you can safely operate these vehicles.
While Idaho does not specifically require specialized experience or training for a CDL Doubles/Triples endorsement, it is highly recommended. Understanding how to handle these types of vehicles, how to couple and uncouple, and inspecting the vehicle are crucial. This knowledge can be gained through hands-on training with a qualified instructor and studying the CDL manual.
Yes, to obtain a CDL Doubles/Triples endorsement in Idaho, you are required to pass the Doubles/Triples Knowledge Test. This written exam focuses on the specific knowledge and skills needed to safely operate double and triple trailers, including coupling and uncoupling, vehicle inspections, and managing cargo.
During the CDL Doubles/Triples endorsement test in Idaho, you won't have to showcase specific driving skills or maneuvers. The test is knowledge-based and covers topics like coupling and uncoupling, inspecting doubles and triples, and managing cargo. However, practical skills like safely driving, turning, and parking these vehicles are crucial for real-world application.
No, it is not permissible to operate double or triple trailers without a valid CDL Doubles/Triples endorsement in Idaho. This endorsement is required by federal and state law to ensure that drivers have the necessary skills and knowledge to safely operate these larger, more complex vehicles. Operating without the endorsement can result in fines and penalties.
You can append the CDL Doubles/Triples endorsement to your current commercial driver's license. You don't need to initiate a new application for a CDL. However, you must pass the Doubles/Triples Knowledge Test. Once passed, the endorsement will be added to your existing CDL.
Drivers with a CDL Doubles/Triples endorsement must adhere to specific rules. These include restrictions on the maximum combined length of the trailers and the requirement to only drive these vehicles on designated highways. Also, they must follow all general CDL regulations, including hours of service rules, vehicle inspection requirements, and maintaining a clean driving record.
In Idaho, the maximum weight for a commercial vehicle, including double or triple trailers, is 105,500 lbs. The maximum length for a double trailer is 61 feet for the two trailers combined. Triple trailers are not generally permitted except on designated highways and they cannot exceed 95 feet in total length. These restrictions can change, so always check the current regulations.
Yes, there are specific safety guidelines for driving double/triple trailers. Drivers must maintain a safe following distance, anticipate stops, and avoid sudden lane changes. They should also be mindful of the "crack-the-whip" effect during turns. Regular vehicle inspections are mandatory to ensure brake system integrity and correct weight distribution. Additionally, drivers must comply with all CDL rules and federal regulations.