Texas CDL - Air Brake Test Questions with Correct Answers and
Answers with Verified Solutions | Latest 2026 Update
Q: What is a dual air brake system?
Answer:
A two brake system, one operates the front brakes and one operates the back brakes.
What are the slack adjusters? It is an adjusting nut on the backside of the brake drum
used for adjusting the brakes. How can you check the slack adjuster? Park on level
ground, turn off the parking brakes, pull hard on each slack adjuster. It shouldn't
move more than one inch. How can you test the low pressure warning signal? Shut
off the engine with enough air pressure, turn on the electrical power and step on and
off the brake pedal until the low air pressure warning signal comes on. What are the
maximum leaking rates? Less than 2 psi in one minute for single vehicles and less
than 3 psi in one minute for combination vehicles. When is it OK to leave your truck
unattended without applying parking brakes or chocking the wheels? Never If you
are away from your vehicle for only a short time you don't need to use the parking
brake. False
, Q: If you do not have automatic tank drains, how often should you drain the oil and
water from the bottom of compressed air storage tanks?
Answer:
At the end of each day of driving The use of brakes on a long steep downgrade is
only a supplement to the braking effect of the engine. True What factors can cause
brakes to face or fail? Over heating, low air pressure, and not relying on the engine
braking effect. Why should you be in the proper gear before starting down a hill? So
you only have to apply the brake just hard enough to feel a definite slowdown. If oil
and water collects in the air tanks what can happen to the brakes? The brakes could
fail What is the purpose of an alcohol evaporator? To reduce the risk of ice in the
brake valves and other parts in cold weather. What is another name for controlled
braking? Squeeze braking The brake chamber fills with air pushing the rod out which
moves the _________ __________, which twists the _________ __________. Slack
adjuster and brake camshaft If your vehicle has an alcohol evaporator you should
check and fill the alcohol level everyday during cold weather. True To test the air
service brakes, you should: Brake firmly while slowly moving forward The driver
must be able to see a low pressure warning which comes on before pressure in the
service air tank falls below: 60 psi
Answers with Verified Solutions | Latest 2026 Update
Q: What is a dual air brake system?
Answer:
A two brake system, one operates the front brakes and one operates the back brakes.
What are the slack adjusters? It is an adjusting nut on the backside of the brake drum
used for adjusting the brakes. How can you check the slack adjuster? Park on level
ground, turn off the parking brakes, pull hard on each slack adjuster. It shouldn't
move more than one inch. How can you test the low pressure warning signal? Shut
off the engine with enough air pressure, turn on the electrical power and step on and
off the brake pedal until the low air pressure warning signal comes on. What are the
maximum leaking rates? Less than 2 psi in one minute for single vehicles and less
than 3 psi in one minute for combination vehicles. When is it OK to leave your truck
unattended without applying parking brakes or chocking the wheels? Never If you
are away from your vehicle for only a short time you don't need to use the parking
brake. False
, Q: If you do not have automatic tank drains, how often should you drain the oil and
water from the bottom of compressed air storage tanks?
Answer:
At the end of each day of driving The use of brakes on a long steep downgrade is
only a supplement to the braking effect of the engine. True What factors can cause
brakes to face or fail? Over heating, low air pressure, and not relying on the engine
braking effect. Why should you be in the proper gear before starting down a hill? So
you only have to apply the brake just hard enough to feel a definite slowdown. If oil
and water collects in the air tanks what can happen to the brakes? The brakes could
fail What is the purpose of an alcohol evaporator? To reduce the risk of ice in the
brake valves and other parts in cold weather. What is another name for controlled
braking? Squeeze braking The brake chamber fills with air pushing the rod out which
moves the _________ __________, which twists the _________ __________. Slack
adjuster and brake camshaft If your vehicle has an alcohol evaporator you should
check and fill the alcohol level everyday during cold weather. True To test the air
service brakes, you should: Brake firmly while slowly moving forward The driver
must be able to see a low pressure warning which comes on before pressure in the
service air tank falls below: 60 psi
