Air Brakes #2
Air Brakes Endorsement Test | Tennessee 2025 #2
Train for FREE online with our Tennessee 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 TN Class A/Class B driver license in 2025, 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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1 . A ____ allows a driver to gradually apply spring brakes.
A modulating control valve allows a driver to gradually apply spring brakes. In equipped vehicles, the valve is controlled by a lever located on the dashboard.
2 . 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.
3 . Some air brake systems use alcohol:
To reduce the risk of rust forming on air brake valves.
Some air brake systems contain an alcohol evaporator. This device introduces alcohol into the braking system to inhibit the formation of ice.
4 . How much distance will an air brake-equipped vehicle need to come to a complete stop if it is traveling at 55 mph under ideal driving conditions?
A vehicle's total stopping distance is made up of perception distance, reaction distance, brake lag distance, and braking distance. With all of these factors included, an air brake-equipped vehicle traveling at a speed of 55 mph under ideal driving conditions will need approximately 450 feet to come to a complete stop.
5 . During an applied leakage test, the maximum leakage rate for a double combination vehicle is ____ in a minute.
It is important to know the maximum air loss rate that is safe for your specific vehicle. A double combination vehicle should have a leakage rate no higher than 4 psi in a minute during an applied leakage test.
6 . Air tank drains:
Must remain open while driving.
Compressed air in an air brake system usually contains a certain amount of water and compressor oil. The water and oil can damage the brakes if left to accumulate in the system. Manually operated air tank drains must be opened daily to remove this build-up.
2025 Tennessee | Frequently Asked Questions
To secure a CDL Doubles/Triples endorsement in Tennessee, you must already have a Commercial Driver’s License (CDL). You will need to pass the Doubles/Triples Knowledge test. Study the relevant section in the TN CDL manual before taking the test. Once you pass, the endorsement will be added to your CDL.
To obtain a CDL Doubles/Triples license, you must have a valid Commercial Driver’s License (CDL). You'll also need to pass the Doubles/Triples Knowledge test. This test covers the specific skills and knowledge needed to safely operate such vehicles. Studying the relevant sections of your state's CDL manual will help you prepare for this test.
While you don't necessarily need specialized experience or training to get a CDL Doubles/Triples endorsement, it's highly recommended. You must pass the Doubles/Triples Knowledge test, so studying the relevant sections of your state's CDL manual is crucial. Some choose to attend a CDL training school for hands-on experience before taking the test.
Yes, to acquire a CDL Doubles/Triples endorsement, you must pass the Doubles/Triples Knowledge test. This test evaluates your knowledge of safely operating double and triple trailers, coupling and uncoupling, inspecting doubles and triples, and more. It's crucial to study the relevant sections of your state's CDL manual thoroughly before taking the test.
The CDL Doubles/Triples endorsement test is primarily a written exam, focusing on your knowledge rather than specific driving maneuvers. It covers areas such as coupling and uncoupling, inspecting doubles and triples, and the specifics of managing these larger vehicles. However, it's beneficial to practice driving these larger vehicles for real-world application of these principles.
No, it is not permissible to operate double/triple trailers without a valid CDL Doubles/Triples endorsement in Tennessee. The state requires drivers to obtain this endorsement to ensure they have the necessary knowledge and skills to safely operate such vehicles. Violating this requirement can result in penalties and potential suspension of driving privileges.
You can add the CDL Doubles/Triples endorsement to your existing commercial driver's license. You don't need to initiate a new application for a separate license. However, you must pass the Doubles/Triples Knowledge test to get this endorsement. It's important to check with your local DMV for specific state requirements and procedures.
Yes, there are limitations. A CDL Doubles/Triples endorsement only permits you to drive vehicles with more than one trailer. However, it doesn't allow you to operate other special vehicle types like buses or tank vehicles unless you have the specific endorsements for those. Also, all federal and state regulations regarding hours of service, vehicle maintenance, and load securement must still be followed.
In Tennessee, the maximum legal weight for a vehicle including double/triple trailers is 80,000 pounds. The maximum length for each semi-trailer is 28 feet 6 inches, and for each full trailer it's 28 feet. However, these restrictions can vary depending on road types and specific routes. Always check local regulations to ensure compliance.
Yes, drivers with a CDL Doubles/Triples endorsement must adhere to specific safety regulations. These include performing routine vehicle inspections, following appropriate coupling and uncoupling procedures, and maintaining safe following distances. They must also understand the high rollover risk associated with these vehicles and the effects of speed and curves on stability. Compliance with these guidelines helps ensure road safety.