T4 ASE BRAKES EXAM STUDY GUIDE
2026/2027 COMPLETE QUESTIONS WITH
VERIFIED CORRECT ANSWERS ||
100% GUARANTEED PASS
<NEWEST VERSION>
1. Psi loss rate for Straight Truck - ANSWER ✔ 2 psi/minute
2. Psi loss rate for combination vehicle - ANSWER ✔ less than 3 psi/minute
3. Service Brake Pressure Drop Test - ANSWER ✔ Apply service brake to 90
psi. Loss rate should be less than 3 psi/minute for straight vehicles and less
than 4 psi/minute for combination vehicles.
4. Improperly adjusted brake shoes - ANSWER ✔ Cause
1) brake imbalance
2) increased stopping distance
3) excessive heat and wear
5. Caging Brake Chamber - ANSWER ✔ 1) require the spring be mechanically
captured to avoid accidental releasing.
6. 2) do not drop spring brake cause the high tension spring may cause
chamber to fly apart.
,7. 3) if spring brake is damaged do not attempt to cage.
8. Parking Brake - ANSWER ✔ 1) Per FMVSS ( Federal Motir Vehicle Safety
Standards) parking brakes must be able to hold a truck, loaded to its gross
weight rating, stationary, on a smooth, dry, concrete roadway, facing uphill
or downhill on a 20% grade
9. 2) In the emergency mode, the parking brakes must be able to exert a
retarding force equal to 28% of the gross axle rating.
10.Push Pull Valves- Yellow - ANSWER ✔ 1) when valve is pushed in air is
supplied to the truck spring brake chambers to release the parking brake.
11.2) when the valve is pulled out, air pressure will exhaust from the spring
brakes, actuating the parking brakes.
12.Hydraulic Brakes Troubleshooting - ANSWER ✔ 1)front of vehicle dives
when brakes applied, suspect a defecting metering or combination valve.
13.2)Rear brakes lock up, suspect out of adjustment load proportioning or
combination valve. this valve provides maximum braking balance based on
trucks payload.
14.Brake Pedal Pushrod - ANSWER ✔ 1) a pushrod with too much travel will
delay master cylinder engagement, leading to poor stopping ability
,15.Brake Lines and Hoses - ANSWER ✔ 1) Most brake line tubing is made of
double wall steel, ranging in diameter of 1/8 in to 3/8 in.
16.2) replace entire brake line if damages are visible with same type, size, shape
and length. Replace cracking or visibly damaged hoses.
17.An air leak at point X in the system shown would would cause which of
these to leak down? - ANSWER ✔ #1 tank only
18.The Driver Vehicle inspection Report (DVIR) should be submitted: -
ANSWER ✔ Daily
19.Which of the following cannot cause a drum on an air braked vehicle to
overheat? - ANSWER ✔ Too high governor cut out pressure
20.All the brakes drag on a truck with hydraulics brakes. Which of the
following could be the cause? - ANSWER ✔ No brake pedal free travel
21.65. Air disc brakes are designed to:
A. apply faster
B. last longer
C. decrease in-lane braking stability
D. none of the above - ANSWER ✔ 65. The correct answer is D.
Air disc brake technology improves in-lane braking stability
as compared to S-Cam brakes. Small variations in lining
friction or the drum surface on Scam brakes can affect braking
stability. Air disc brakes are designed to minimize this
instability as pressure is applied constantly and efficiently to
all wheels.
, 22.66. The right front wheel of a truck with hydrau anti-lock brakes locks up
when on a slippery s Technician A says the truck could have a defec wheel
sensor. Technician B says the sensor ch for a lock-up condition and sends a
signal to th draulic modulator. Who is right?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B - ANSWER ✔ 66. The correct answer is C,
both Technicians are right.
Hydraulic anti-lock systems use a control module in conjunction with wheel
speed sensors to establish the deceleration rate of the vehicle's wheels during
braking. If the control module determines that wheel lock-up is about to take
place, it will issue commands to a hydraulic modula-tor. The modulator will
then regulate fluid pressure to the wheels as instructed.
23.67. New generation ABS systems are designed to:
A. allow the driver to apply with more foot pressure
B. allow the pedal to be pumped
C. default to non-ABS when a failure is detected
D. none of the above - ANSWER ✔ 67. The correct answer is C.
All new-generation anti-lock systems are designed to default
to what is typically called a 'fail soft condition--that is, when
there is an ABS mal-function, the brake system simply
behaves as though there was no ABS.
24.68. A truck with air brakes takes an inordinate time to build up adequate air
pressure. Oil has been found in the air brake system. Technician A says the
compressor air filter could be clogged. Technician B says the compressor oil
control rings could be worn. Who is right?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B - ANSWER ✔ 68. The correct answer is C,
both Technicians are right.
2026/2027 COMPLETE QUESTIONS WITH
VERIFIED CORRECT ANSWERS ||
100% GUARANTEED PASS
<NEWEST VERSION>
1. Psi loss rate for Straight Truck - ANSWER ✔ 2 psi/minute
2. Psi loss rate for combination vehicle - ANSWER ✔ less than 3 psi/minute
3. Service Brake Pressure Drop Test - ANSWER ✔ Apply service brake to 90
psi. Loss rate should be less than 3 psi/minute for straight vehicles and less
than 4 psi/minute for combination vehicles.
4. Improperly adjusted brake shoes - ANSWER ✔ Cause
1) brake imbalance
2) increased stopping distance
3) excessive heat and wear
5. Caging Brake Chamber - ANSWER ✔ 1) require the spring be mechanically
captured to avoid accidental releasing.
6. 2) do not drop spring brake cause the high tension spring may cause
chamber to fly apart.
,7. 3) if spring brake is damaged do not attempt to cage.
8. Parking Brake - ANSWER ✔ 1) Per FMVSS ( Federal Motir Vehicle Safety
Standards) parking brakes must be able to hold a truck, loaded to its gross
weight rating, stationary, on a smooth, dry, concrete roadway, facing uphill
or downhill on a 20% grade
9. 2) In the emergency mode, the parking brakes must be able to exert a
retarding force equal to 28% of the gross axle rating.
10.Push Pull Valves- Yellow - ANSWER ✔ 1) when valve is pushed in air is
supplied to the truck spring brake chambers to release the parking brake.
11.2) when the valve is pulled out, air pressure will exhaust from the spring
brakes, actuating the parking brakes.
12.Hydraulic Brakes Troubleshooting - ANSWER ✔ 1)front of vehicle dives
when brakes applied, suspect a defecting metering or combination valve.
13.2)Rear brakes lock up, suspect out of adjustment load proportioning or
combination valve. this valve provides maximum braking balance based on
trucks payload.
14.Brake Pedal Pushrod - ANSWER ✔ 1) a pushrod with too much travel will
delay master cylinder engagement, leading to poor stopping ability
,15.Brake Lines and Hoses - ANSWER ✔ 1) Most brake line tubing is made of
double wall steel, ranging in diameter of 1/8 in to 3/8 in.
16.2) replace entire brake line if damages are visible with same type, size, shape
and length. Replace cracking or visibly damaged hoses.
17.An air leak at point X in the system shown would would cause which of
these to leak down? - ANSWER ✔ #1 tank only
18.The Driver Vehicle inspection Report (DVIR) should be submitted: -
ANSWER ✔ Daily
19.Which of the following cannot cause a drum on an air braked vehicle to
overheat? - ANSWER ✔ Too high governor cut out pressure
20.All the brakes drag on a truck with hydraulics brakes. Which of the
following could be the cause? - ANSWER ✔ No brake pedal free travel
21.65. Air disc brakes are designed to:
A. apply faster
B. last longer
C. decrease in-lane braking stability
D. none of the above - ANSWER ✔ 65. The correct answer is D.
Air disc brake technology improves in-lane braking stability
as compared to S-Cam brakes. Small variations in lining
friction or the drum surface on Scam brakes can affect braking
stability. Air disc brakes are designed to minimize this
instability as pressure is applied constantly and efficiently to
all wheels.
, 22.66. The right front wheel of a truck with hydrau anti-lock brakes locks up
when on a slippery s Technician A says the truck could have a defec wheel
sensor. Technician B says the sensor ch for a lock-up condition and sends a
signal to th draulic modulator. Who is right?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B - ANSWER ✔ 66. The correct answer is C,
both Technicians are right.
Hydraulic anti-lock systems use a control module in conjunction with wheel
speed sensors to establish the deceleration rate of the vehicle's wheels during
braking. If the control module determines that wheel lock-up is about to take
place, it will issue commands to a hydraulic modula-tor. The modulator will
then regulate fluid pressure to the wheels as instructed.
23.67. New generation ABS systems are designed to:
A. allow the driver to apply with more foot pressure
B. allow the pedal to be pumped
C. default to non-ABS when a failure is detected
D. none of the above - ANSWER ✔ 67. The correct answer is C.
All new-generation anti-lock systems are designed to default
to what is typically called a 'fail soft condition--that is, when
there is an ABS mal-function, the brake system simply
behaves as though there was no ABS.
24.68. A truck with air brakes takes an inordinate time to build up adequate air
pressure. Oil has been found in the air brake system. Technician A says the
compressor air filter could be clogged. Technician B says the compressor oil
control rings could be worn. Who is right?
A. Technician A
B. Technician B
C. Both A and B
D. Neither A or B - ANSWER ✔ 68. The correct answer is C,
both Technicians are right.
