Air Brakes #1
Air Brakes Endorsement Test | Texas 2025 #1 Page 2 of 4
Train for FREE online with our Texas 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 TX 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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7 . Which of the following is not a part of an air brake system?
An axle brake system
Air brakes consists of three separate braking systems: the service brake system, the parking brake system, and the emergency brake system.
8 . Friction inside a brake drum is caused when the brake shoes and linings:
Create excess heat.
Friction inside a brake drum is caused when the brake shoes and linings push against the inside of the drum. The friction in the drums will slow and stop the vehicle.
9 . During a static leakage test, the maximum leakage rate for a single vehicle with air brakes is ____ in one minute.
4 psi
When performing a static leakage test on a single vehicle with air brakes, the leakage rate should be no more than 2 psi in a minute. If air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.
10 . A dual air brake system:
Has two separate air brake systems, but uses a single set of controls.
A dual air brake system has two separate air brake systems that use a single set of brake controls. One system typically operates the regular brakes on the rear axle or axles. The other system operates the regular brakes on the front axle.
11 . During a static leakage test, the maximum leakage rate for a double combination vehicle is:
4 psi in one minute.
When performing a static leakage test on a double combination vehicle with air brakes, the leakage rate should be no more than 3 psi in one minute. If air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.
12 . To ensure normal stopping power, drivers of vehicles equipped with a front brake limiting valve should:
Keep the control at the halfway mark.
Some pre-1975 vehicles have a front brake limiting valve, which has "normal" and "slippery" settings. The idea behind these valves was to limit the air pressure available to the front brakes when driving on slippery surfaces, and thereby reduce the danger of a front-wheel skid. Studies have found that this is not actually a concern, so if your vehicle has a front brake limiting valve, leave it in the "normal" position.
2025 Texas | Frequently Asked Questions
A CDL Class A license in Texas permits drivers to operate any combination of vehicles with a Gross Combination Weight Rating (GCWR) of 26,001 pounds or more, provided the Gross Vehicle Weight Rating (GVWR) of the vehicle(s) being towed is over 10,000 pounds. It covers vehicles like tractor-trailers, truck and trailer combinations, and tank vehicles.
A Class A CDL license in Texas allows the holder to operate vehicles such as tractor-trailers, truck and trailer combinations, tank vehicles, livestock carriers, and flatbeds. These are typically vehicles with a Gross Combination Weight Rating (GCWR) of 26,001 pounds or more where the towed vehicle exceeds 10,000 pounds.
To obtain a Class A CDL license in Texas, you must be at least 18 years old (21 for interstate driving), possess a valid Texas driver's license, pass a vision exam, and successfully complete both a written knowledge test and a three-part skills test. Additionally, you must provide proof of citizenship or lawful presence and pass a medical examination.
In Texas, you must be at least 18 years old to qualify for a Class A CDL license for intrastate driving (within Texas only). However, to drive a commercial vehicle across state lines (interstate), federal regulations require drivers to be at least 21 years old.
Specific endorsements are not required for a Class A CDL license, but they can provide additional driving privileges. Endorsements include T for double/triple trailers, P for passenger vehicles, N for tank vehicles, H for hazardous materials, and S for school buses. Each endorsement requires passing additional written and/or skills tests.
The Class A CDL skills test in Texas includes three parts: a pre-trip vehicle inspection, a basic vehicle control test, and an on-road driving test. These are designed to assess your ability to safely operate and maintain a Class A commercial vehicle. The test must be taken in a vehicle representative of the one you'll be driving.
Yes, there can be limitations for Class A CDL license holders. These are called restrictions and are marked on the license. For example, if you cannot operate a manual transmission, you may have an automatic only restriction. If you don't pass the air brakes test, your license will show you're not permitted to drive vehicles with air brakes.
Yes, it is possible to take the written Class A CDL test in languages other than English in Texas. However, the Department of Public Safety recommends that applicants have a basic understanding of English due to the English Language Proficiency requirement, which mandates drivers understand traffic signs and signals in English.
Yes, you can request accommodations for the Class A CDL written test if you have a disability. Texas Department of Public Safety provides reasonable testing accommodations according to the Americans with Disabilities Act. However, you must provide adequate documentation of your disability and you may need to make the request in advance.
Yes, if you don't pass the Class A CDL written test in Texas, you can retake it. However, you must wait at least one day before retesting. If you fail the test three times, you are required to wait 30 days before retesting. After failing six times, you must wait 90 days. Each retake does require an additional fee.