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CDL Air Brakes Endorsement Practice Test -5

Pass your CDL Air Brake Test with ease. Start here by taking this Free 25 question practice test, every question and answer is straight out of the Commercial Drivers License Handbook.
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CDL Air Brakes Endorsement Practice Test

Ace your air brakes endorsement exam by prepping with a free comprehensive air brakes test! If you’re seeking an air brakes endorsement on your commercial driver’s license, you’ll need to learn additional procedures and laws to safely drive these vehicles—such as how long a truck can hold air pressure, the number of steps used in an air brake system, how to drain air tanks, and more. This free practice test includes air brakes-specific information that you’ll see on your actual DMV exam.

There are 25 multiple-choice questions taken directly from the FMCSA air brakes regulations. You’ll benefit from the same format you’ll experience during your actual DMV exam, and you can retake the test as many times as you need to feel fully prepared. Plus, see your missed questions in real time and review them as a group at the end of your test, so you know exactly which areas to revisit for further study.

CDL Air Brakes Endorsement Practice Test FAQs:

What’s the difference between the CDL permit test and the CDL air brakes test?

The CDL permit test is an exam that all commercial drivers must take in order to receive a CDL. The air brakes exam is an additional test required for drivers wanting to earn an air brakes endorsement on your CDL, which is necessary to drive vehicles that use air brakes.

What does the air brakes test consist of?

The air brakes test consists of a written exam as well as a practical demonstration showing your knowledge and understanding of driving a vehicle equipped with air brakes. Each state's DMV sets its own number of questions for the test, but they all use information from the Federal Motor Carrier Safety Administration (FMCSA) laws and regulations for commercial drivers.

Is the air brakes endorsement required for all commercial drivers?

No, an air brakes endorsement is only required if you’re planning to drive vehicles equipped with air brakes.

[permit_quiz:state:entity:title] [permit_quiz:state:entity:field_agency_shortname] Sample Test Questions

An application pressure gauge shows how much air you are applying to the brakes. Increased application pressure to maintain the same speed indicates that __________.
  • The brakes are working correctly.
  • The brakes are fading.
  • The engines are failing.
  • The clutch is stuck.
How do you check the low pressure warning signal?
  • Shut off the engine when the low pressure warning signal is not on. Turn the electrical power on and step on and off the brake pedal to reduce air tank pressure.
  • Step on the brake pedal hard until the wheels lock.
  • Wait until the low pressure warning signal comes on, then turn off the engine immediately. Turn it back on and see if the low-pressure warning is still on.
  • None of the listed answers.
How does excessive heat affect service brakes?
  • To fade.
  • Chemical changes in the brake lining.
  • To fail.
  • All of the listed answers.
If a vehicle has a dual air brake system _______.
  • There will be only one gauge.
  • Three supply pressure gauges are necessary.
  • There will be a gauge for each half of the system.
  • None of the listed answers.
It's important that a warning signal comes on before the air pressure in the tank falls below _______.
  • 125 psi.
  • 100 psi.
  • 90 psi.
  • 120 psi.
  • 60 psi.