Free Oregon CDL Air Brakes Practice Test 2023

Do you need an Oregon Air Brakes endorsement or an L endorsement for your commercial driving license? The Oregon CDL Air Brake has some differences from other endorsements because your license will receive a mark of restriction if you fail the test. So having good preparation before exam day is very necessary. To ensure that our questions are relevant, all of our CDL practice test packs are based on the Oregon CDL manual. Each question has a detailed explanation for you to thoroughly learn the format and the topic. Don't be afraid of having a restriction on your license. Let’s try our Oregon CDL Practice Test to get ready to pass the Oregon CDL Air Brake Test now. 

Our CDL practice tests:
Based on 2021 OR commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
OR CDL Air Brakes Test format:
25 questions
20 correct answers to pass
80% passing score
List of questions
What can legally hold a parking or emergency brake in position for a truck, truck tractor, or bus?
When is it OK to leave your truck unattended without applying the parking brakes and choking the wheels?
How far should manual slack adjusters move before they need to be adjusted?
A dual air brake system ________.
If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build up from 85 to 100 psi within how many seconds?
In a controlled braking emergency:
The brake system that applies and releases the brakes when the driver uses the brake pedal is the ________ brake system.
Spring brakes will generally come on at:
While applying the brakes, what tells the driver how much air pressure is being used?
With air brake vehicles, the parking brake should be used:
To stop the vehicle, air brakes systems use:
Normally during anti-lock braking, the driver:
When you need to apply more pressure to help your brakes work normally effectively, this means that your brakes are fading. Which of the following can cause fading brakes?
The type of brakes that clamp the rotor between the brake shoes is:
When does the air compressor governor allow air to start pumping?
If you are driving down a steep downgrade and have reached your safe speed of 40 mph, you would apply the service brake until your speed dropped to ____ mph.
Repeatedly partially increasing and pressing the brake pedal may result in:
Controlled braking is only possible _________.
The most common type of foundation brake is?
In dual air systems, how long should it take air pressure to build 85 to 100 psi?
Why should you check the brake adjustment often?
If air supply drops when driving, the tractor protection valve ________.
On large buses low pressure warning devices usually signal at ______.
What is a wig wag ?
Water and oil _______.