© EVERLY 2025 ALL RIGHTS RESERVED.
CDL Air Brakes Questions And Answers
100% Pass.
Air loss in a straight truck or bus should not be more than how much PSI with the engine off and
the brakes on? - Answer✔3 PSI in one minute
To make an emergency stop with air brakes, using the stab braking method, you should -
Answer✔Brake as hard as you can
get off brakes when wheels lock
get back on brakes when wheels start rolling again
All vehicles with air brakes must have what signal? - Answer✔Low air pressure warning signal
It is accepted that too much heat caused by using your brakes too often can also cause what? -
Answer✔brake to fade or fail
When is it ok to leave your truck unattended without applying the parking brakes and choking
the wheels? - Answer✔Never
You should know that your brakes are fading when you have to do what? - Answer✔push harder
on the brake pedal to control your speed on a downgrade
The safety valve discharges automatically at what pressure? - Answer✔150
What is a dual airbrake system? - Answer✔2 brake system
one operates front brakes
one operates back brakes
If air pressure is not built up within the correct amount of time, then what will happen? -
Answer✔air pressure may drop to a low point while driving, requiring an emergency stop
How often should you drain air tanks? - Answer✔Daily
, © EVERLY 2025 ALL RIGHTS RESERVED.
A slack adjusters free play needs to be adjusted if it is more than about how many inches when
you pull hard on it? - Answer✔1 inch
In ideal conditions, a truck or bus with an air brake going at 55 mph would require a stopping
distance of how many feet? - Answer✔more than 300 feet
If air pressure is not built up within the correct amount of time, then what will happen to the air
pressure? - Answer✔drop to a low point while driving
requiring an emergency stop
It is accepted that too much heat caused by using your brakes too often can also cause what? -
Answer✔Brake to fade or fail
What does the governor control? - Answer✔when air compressor will pump into air storage
tanks
To make an emergency stop with air brakes, using the stab braking method, you should do what?
- Answer✔Brake as hard as you can
get off brakes when wheels lock
get back on brakes when wheels start rolling
The driver must be able to see a low air pressure warning which comes on before pressure in the
service air tanks falls below what PSI? - Answer✔60
The use of brakes on a long steep downgrade is only a supplement to the braking effect of the
engine - Answer✔True
The spring brakes used on the chambers in a straight truck will bring you to a stop when air
pressure drops below what PSI? - Answer✔60
What do air brakes use to make the brakes work? - Answer✔Compressed Air
What can legally hold a parking or emergency brake in position for a truck, truck tractor, or bus?
- Answer✔Spring Pressure
When you put on the brakes by pushing down the brake pedal, what happens? - Answer✔Air
pressure is applied to the brake pads
Air loss in a straight truck or bus should not be more than what with the engine off and the
brakes on? - Answer✔3 PSI in one Minute
What does the Emergency Brake System do? - Answer✔Uses part of the service and parking
brake system to stop the vehicle in the event of a brake system failure
CDL Air Brakes Questions And Answers
100% Pass.
Air loss in a straight truck or bus should not be more than how much PSI with the engine off and
the brakes on? - Answer✔3 PSI in one minute
To make an emergency stop with air brakes, using the stab braking method, you should -
Answer✔Brake as hard as you can
get off brakes when wheels lock
get back on brakes when wheels start rolling again
All vehicles with air brakes must have what signal? - Answer✔Low air pressure warning signal
It is accepted that too much heat caused by using your brakes too often can also cause what? -
Answer✔brake to fade or fail
When is it ok to leave your truck unattended without applying the parking brakes and choking
the wheels? - Answer✔Never
You should know that your brakes are fading when you have to do what? - Answer✔push harder
on the brake pedal to control your speed on a downgrade
The safety valve discharges automatically at what pressure? - Answer✔150
What is a dual airbrake system? - Answer✔2 brake system
one operates front brakes
one operates back brakes
If air pressure is not built up within the correct amount of time, then what will happen? -
Answer✔air pressure may drop to a low point while driving, requiring an emergency stop
How often should you drain air tanks? - Answer✔Daily
, © EVERLY 2025 ALL RIGHTS RESERVED.
A slack adjusters free play needs to be adjusted if it is more than about how many inches when
you pull hard on it? - Answer✔1 inch
In ideal conditions, a truck or bus with an air brake going at 55 mph would require a stopping
distance of how many feet? - Answer✔more than 300 feet
If air pressure is not built up within the correct amount of time, then what will happen to the air
pressure? - Answer✔drop to a low point while driving
requiring an emergency stop
It is accepted that too much heat caused by using your brakes too often can also cause what? -
Answer✔Brake to fade or fail
What does the governor control? - Answer✔when air compressor will pump into air storage
tanks
To make an emergency stop with air brakes, using the stab braking method, you should do what?
- Answer✔Brake as hard as you can
get off brakes when wheels lock
get back on brakes when wheels start rolling
The driver must be able to see a low air pressure warning which comes on before pressure in the
service air tanks falls below what PSI? - Answer✔60
The use of brakes on a long steep downgrade is only a supplement to the braking effect of the
engine - Answer✔True
The spring brakes used on the chambers in a straight truck will bring you to a stop when air
pressure drops below what PSI? - Answer✔60
What do air brakes use to make the brakes work? - Answer✔Compressed Air
What can legally hold a parking or emergency brake in position for a truck, truck tractor, or bus?
- Answer✔Spring Pressure
When you put on the brakes by pushing down the brake pedal, what happens? - Answer✔Air
pressure is applied to the brake pads
Air loss in a straight truck or bus should not be more than what with the engine off and the
brakes on? - Answer✔3 PSI in one Minute
What does the Emergency Brake System do? - Answer✔Uses part of the service and parking
brake system to stop the vehicle in the event of a brake system failure
