TEXAS CDL AIR BRAKES EXAM, PRACTICE EXAM AND
STUDY GUIDE NEWEST 2025 ACTUAL EXAM 60
QUESTIONS AND CORRECT DETAILED ANSWERS
Air brake systems combine what three different systems? -CORRECT ANSWER
Service brakes, parking brakes and emergency brakes.
When should you drain the air tanks? -CORRECT ANSWER After every working day.
Why drain water from the compressed air tanks? -CORRECT ANSWER Water can
freeze in cold weather and cause brake failure.
Air brake equipped vehicles must have: -CORRECT ANSWER A supply pressure
gauge and warning signal when psi drops below 60.
What can legally hold a parking or emergency brake in position for a truck, truck tractor
or bus? -CORRECT ANSWER Spring pressure.
What makes the total stopping distance for air brakes longer than that for hydraulic
brakes? -CORRECT ANSWER Brake lag distance.
The first thing you should do when the low air pressure warning comes on? -CORRECT
ANSWER Stop and safely park ASAP.
The braking power of the spring brakes: -CORRECT ANSWER Depends on the
adjustment of the service brakes.
The air compressor governor controls what? -CORRECT ANSWER When air is
pumped into the air tanks.
The application pressure gauge shows the driver how much pressure: -CORRECT
ANSWER Is being applied to the brakes.
When you apply pressure to the brake pedal, you are... -CORRECT ANSWER Pushing
against a spring and against air pressure to the brakes.
The air compressor is connected to the engine through... -CORRECT ANSWER Gears
or a V-belt
Which type of brake is the most common in commercial vehicles? -CORRECT
ANSWER S-cam brake
, An application pressure gauge... -CORRECT ANSWER Shows how much air pressure
you are applying to the brakes.
All vehicles with air brakes are required to have a low pressure warning signal. This
could be... -CORRECT ANSWER A red light, wig wag mechanical arm or a buzzer.
To test service brakes you should... -CORRECT ANSWER Release the parking brake,
move forward slowly and depress brakes.
Stab braking occurs when you... -CORRECT ANSWER 1. Press on a brake pedal as
hard as you can. 2. Release the brakes when the wheels lock up. 3. Apply the brakes
when the wheels start rolling.
Air brakes take longer to stop than hydraulic brakes because... -CORRECT ANSWER It
takes longer for the air to flow through the lines.
The proper way to go down long grades is to... -CORRECT ANSWER Apply brakes just
hard enough to reduce speed to 5 mph below safe speed then release until back to safe
speed and repeat process.
When should you avoid using the parking brake? -CORRECT ANSWER When the
brakes are hot.
If your vehicle has an alcohol evaporator, everyday during cold weather you should: -
CORRECT ANSWER Check and fill the alcohol level.
During normal driving, spring brakes are usually he'd back by what? -CORRECT
ANSWER Air pressure
In air brake vehicles, the parking brakes should be used when? -CORRECT ANSWER
Whenever the vehicle is parked.
The brake pedal in an air brake system does what? -CORRECT ANSWER Controls the
air pressure applied to put on the brakes.
If your bus has dual parking control valves it means that you can use pressure from a
separate tank to: -CORRECT ANSWER Release the spring brakes to move a short
distance.
A straight truck or bus air brake system should not leak at a rate of more than ____ PSI
per minute with the engine off and the brakes released. -CORRECT ANSWER 2
An alcohol evaporator does what? -CORRECT ANSWER Reduces the risk of ice in the
air brake valves in cold weather.
STUDY GUIDE NEWEST 2025 ACTUAL EXAM 60
QUESTIONS AND CORRECT DETAILED ANSWERS
Air brake systems combine what three different systems? -CORRECT ANSWER
Service brakes, parking brakes and emergency brakes.
When should you drain the air tanks? -CORRECT ANSWER After every working day.
Why drain water from the compressed air tanks? -CORRECT ANSWER Water can
freeze in cold weather and cause brake failure.
Air brake equipped vehicles must have: -CORRECT ANSWER A supply pressure
gauge and warning signal when psi drops below 60.
What can legally hold a parking or emergency brake in position for a truck, truck tractor
or bus? -CORRECT ANSWER Spring pressure.
What makes the total stopping distance for air brakes longer than that for hydraulic
brakes? -CORRECT ANSWER Brake lag distance.
The first thing you should do when the low air pressure warning comes on? -CORRECT
ANSWER Stop and safely park ASAP.
The braking power of the spring brakes: -CORRECT ANSWER Depends on the
adjustment of the service brakes.
The air compressor governor controls what? -CORRECT ANSWER When air is
pumped into the air tanks.
The application pressure gauge shows the driver how much pressure: -CORRECT
ANSWER Is being applied to the brakes.
When you apply pressure to the brake pedal, you are... -CORRECT ANSWER Pushing
against a spring and against air pressure to the brakes.
The air compressor is connected to the engine through... -CORRECT ANSWER Gears
or a V-belt
Which type of brake is the most common in commercial vehicles? -CORRECT
ANSWER S-cam brake
, An application pressure gauge... -CORRECT ANSWER Shows how much air pressure
you are applying to the brakes.
All vehicles with air brakes are required to have a low pressure warning signal. This
could be... -CORRECT ANSWER A red light, wig wag mechanical arm or a buzzer.
To test service brakes you should... -CORRECT ANSWER Release the parking brake,
move forward slowly and depress brakes.
Stab braking occurs when you... -CORRECT ANSWER 1. Press on a brake pedal as
hard as you can. 2. Release the brakes when the wheels lock up. 3. Apply the brakes
when the wheels start rolling.
Air brakes take longer to stop than hydraulic brakes because... -CORRECT ANSWER It
takes longer for the air to flow through the lines.
The proper way to go down long grades is to... -CORRECT ANSWER Apply brakes just
hard enough to reduce speed to 5 mph below safe speed then release until back to safe
speed and repeat process.
When should you avoid using the parking brake? -CORRECT ANSWER When the
brakes are hot.
If your vehicle has an alcohol evaporator, everyday during cold weather you should: -
CORRECT ANSWER Check and fill the alcohol level.
During normal driving, spring brakes are usually he'd back by what? -CORRECT
ANSWER Air pressure
In air brake vehicles, the parking brakes should be used when? -CORRECT ANSWER
Whenever the vehicle is parked.
The brake pedal in an air brake system does what? -CORRECT ANSWER Controls the
air pressure applied to put on the brakes.
If your bus has dual parking control valves it means that you can use pressure from a
separate tank to: -CORRECT ANSWER Release the spring brakes to move a short
distance.
A straight truck or bus air brake system should not leak at a rate of more than ____ PSI
per minute with the engine off and the brakes released. -CORRECT ANSWER 2
An alcohol evaporator does what? -CORRECT ANSWER Reduces the risk of ice in the
air brake valves in cold weather.
