Do you need an Oklahoma Air Brakes endorsement or an L endorsement for your commercial driving license? The Oklahoma 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 Oklahoma 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 Oklahoma CDL Practice Test to get ready to pass the Oklahoma CDL Air Brake Test now. 

Our CDL practice tests:
Based on 2022 OK commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
OK CDL Air Brakes Test format:
25 questions
20 correct answers to pass
80% passing score
List of questions
1.
The air compressor stops pumping air at what psi?
2.
The safety valve discharges automatically at the pressure of:
3.
The air loss rate for a straight truck or bus with the engine off and the brakes on should not be more than:
4.
A low air pressure warning signal is ________.
5.
"A slack adjuster’s free play needs to be adjusted if it is more than about ______ when you pull hard on it."
6.
An application pressure gauge shows how much air you are applying to the brakes. Increased application pressure to maintain the same speed indicates that __________.
7.
Total stopping distance for air brakes is longer than that for hydraulic brakes due to ______ distance.
8.
The ____ shows how much pressure is in the air tanks.
9.
When should the spring brakes activate?
10.
Another name for the brake pedal is the "foot valve", or:
11.
Which braking system applies and releases the parking brakes when you use the parking brake control?
12.
When you need to depress the brakes harder and harder just to maintain the same speed this means ______.
13.
The safety valve is set automatically when pressure is:
14.
The safety valve reduces pressure at ___ psi.
15.
Which of these is NOT a proper time to apply the parking brakes?
16.
Total stopping distance with air brakes is Perception distance + Braking Distance + Brake Lag Distance +:
17.
In case of emergency stops, drivers should:
18.
A device that limits the amount of air provided to the front brakes is a:
19.
How are brakes designed?
20.
Brake linings should not be _______.
21.
Stop light switches are necessary because ________.
22.
Spring brakes are applied:
23.
The warning light and buzzer will come on when the air pressure in either system drops below what psi?
24.
If your brakes are wet, what should you do to dry them quicker?
25.
What happens when pressure is put on the air brakes?