# 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
Perfect for first-time, renewal applicants
OR CDL Air Brakes Test format:
25 questions
80% passing score
List of questions
1.
Air brakes consist of ________.
2.
When inspecting air brakes:
3.
The safety valve discharges automatically at the pressure of:
4.
An air brake system is fully charged at what psi?
5.
The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below ___ psi.
6.
The supply pressure gauge shows how much pressure:
7.
The main factor in causing brake fade is:
8.
9.
To make sure that the spring brakes come on automatically, do all of the following except:
10.
When testing air leakage rates for single vehicles, initial loss rate should be less than:
11.
When the safety valve releases air this indicates ___________.
12.
Another name for the brake pedal is the "foot valve", or:
13.
What should a driver do when the low air pressure warning signal comes on?
14.
Some vehicles are equipped with a control allowing you to apply the spring brakes gradually, called a:
15.
If your truck has a dual air brake system, and one of the systems is low on pressure:
16.
A device that limits the amount of air provided to the front brakes is a:
17.
Brake drums (or discs) must not have cracks longer than ____ the width of the friction area.
18.
If one air system is very low on pressure _______.
19.
If your vehicle has an alcohol evaporator, the evaporator's purpose is to _____.
20.