CDL Air Brake Practice Test EXAM QUESTIONS WITH COMPLETE
CDL Air Brake Practice Test
SOLUTION) (MULTIPLE CHOICES) (A+ GRADED 100% VERIFIED)
Study online at https://quizlet.com/_2od8ci
LATEST VERSION 2025
1. The parking or emergency brake on a heavy vehicle b. Spring pressure
can only be held in position by something that cannot
leak away, like:
a. Fluid pressure
b. Spring pressure
c. Air pressure
d. Any of the above
2. A straight truck or bus air brake system should not leak c. 3
at a rate of more than __ psi per minute with the engine
off and the brake released.
a. 1
b. 2
c. 3
d. 4
3. Your vehicle has dual air brake system. If low air pres- a. Bring the vehicle to
sure warning comes on for the secondary system or a safe stop and continue
for one system, you should: only when the system is
fixed.
a. Bring the vehicle to a safe stop and continue only
when the system is fixed.
b. Reduce your speed, and test the remaining system
while under-way.
c. Reduce your speed, and drive to the nearest garage
for repairs.
d. Continue at normal speed if only the secondary
system fails.
4. If your vehicle has an alcohol evaporator, it is there to:
1/9
, CDL Air Brake Practice Test
Study online at https://quizlet.com/_2od8ci
a. Rid the wet tank of alcohol that condenses and sits d. Reduce the risk of ice in
at the bottom. the air brake valves in cold
b. Eliminate the need for daily tank draining. weather.
c. Boost tank pressure the same way that supercharg-
ers boost engines.
d. Reduce the risk of ice in the air brake valves in cold
weather.
5. Air braking takes more time than hydraulic because b. Takes more time to flow
air: through the lines than hy-
draulic fluid.
a. Brakes use different brake drums.
b. Takes more time to flow through the lines than
hydraulic fluid.
c. Brakes require heavier return springs.
d. Is always leaking through airline fittings.
6. The brake pedal in an air brake system: c. Controls the air pres-
sure applied to put on the
a. Controls the speed of the air compressor. brakes.
b. Always needs to be held down halfway during nor-
mal driving.
c. Controls the air pressure applied to put on the
brakes.
d. Is connected to slack adjusters by a series of rods
and linkages.
7. With air brake vehicles, the parking brakes should be a. Whenever you leave the
used: vehicle unattended.
a. Whenever you leave the vehicle unattended.
b. To hold your speed when going downhill.
2/9
CDL Air Brake Practice Test
SOLUTION) (MULTIPLE CHOICES) (A+ GRADED 100% VERIFIED)
Study online at https://quizlet.com/_2od8ci
LATEST VERSION 2025
1. The parking or emergency brake on a heavy vehicle b. Spring pressure
can only be held in position by something that cannot
leak away, like:
a. Fluid pressure
b. Spring pressure
c. Air pressure
d. Any of the above
2. A straight truck or bus air brake system should not leak c. 3
at a rate of more than __ psi per minute with the engine
off and the brake released.
a. 1
b. 2
c. 3
d. 4
3. Your vehicle has dual air brake system. If low air pres- a. Bring the vehicle to
sure warning comes on for the secondary system or a safe stop and continue
for one system, you should: only when the system is
fixed.
a. Bring the vehicle to a safe stop and continue only
when the system is fixed.
b. Reduce your speed, and test the remaining system
while under-way.
c. Reduce your speed, and drive to the nearest garage
for repairs.
d. Continue at normal speed if only the secondary
system fails.
4. If your vehicle has an alcohol evaporator, it is there to:
1/9
, CDL Air Brake Practice Test
Study online at https://quizlet.com/_2od8ci
a. Rid the wet tank of alcohol that condenses and sits d. Reduce the risk of ice in
at the bottom. the air brake valves in cold
b. Eliminate the need for daily tank draining. weather.
c. Boost tank pressure the same way that supercharg-
ers boost engines.
d. Reduce the risk of ice in the air brake valves in cold
weather.
5. Air braking takes more time than hydraulic because b. Takes more time to flow
air: through the lines than hy-
draulic fluid.
a. Brakes use different brake drums.
b. Takes more time to flow through the lines than
hydraulic fluid.
c. Brakes require heavier return springs.
d. Is always leaking through airline fittings.
6. The brake pedal in an air brake system: c. Controls the air pres-
sure applied to put on the
a. Controls the speed of the air compressor. brakes.
b. Always needs to be held down halfway during nor-
mal driving.
c. Controls the air pressure applied to put on the
brakes.
d. Is connected to slack adjusters by a series of rods
and linkages.
7. With air brake vehicles, the parking brakes should be a. Whenever you leave the
used: vehicle unattended.
a. Whenever you leave the vehicle unattended.
b. To hold your speed when going downhill.
2/9
