ASE T4 TEST |ACTUAL QUESTIONS AND VERIFIED
ANSWERS|BRAND NEW 2026-2027
UPDATE|GRADED A+
Question 1
Which of the following could cause the brakes on a truck to wear too fast?
A. Glazed Drums
B. Wrong linings installed
C. Low air pressure in the service tanks
D. Governor cut-out pressure too high
CORRECT ANSWER
Answer A is incorrect. Glazed drum linings are hard and do not wear. They also do not stop
the truck.
Answer B is correct. The wrong lining for the application may be the problem.
Answer C is incorrect. Low air pressure in the tanks would not cause brake wear. It may
cause a low amount of reserve air in case of multiple brake applications.
Answer D is incorrect. High governor cut=out pressure may cause the safety valve to open,
but would not cause the brakes to wear too fast.
Question 2
Which of the following could case one brake on a truck to wear faster than the others?
A. Mismatched service brake chambers
B. Mismatched parking brake chambers
C. Low air pressure in the service tanks
D. Governor cut-out pressure too low
CORRECT ANSWER
1
,Answer A is correct. Mismatched brake service chambers would apply unequal brake
application pressure from side to side, which would cause one brake to wear faster.
Answer B is incorrect. Mismatched parking brake chambers would not cause brake wear. It
would possibly allow the brake to roll when parked, because one side could have insufficient
parking brake application.
Answer C is incorrect. Low air pressure in the tanks would not cause brake wear. It may
cause a low amount of reserve air in case of multiple brake applications
Answer D is incorrect. Low governor cut-out pressure may cause an inadequate amount of
air in reserve but would not cause the brake to wear too fast.
Question 3
There is an audible air leak from under the dash when the foot valve is applied. Technician
A says the double-check valve may be faulty. Technician B says the single-check valve may
be
faulty. Who is correct?
CORRECT ANSWER
A. A only
B. B only
C. Both A and B
D. Neither A nor B
Answer A is correct. A leaking double check valve could allow air to flow to the foot valve
and out the open exhaust
Answer B is incorrect. Single check valves are used to protect the tanks. They do not cause
an air leak when the brakes are applied.
Answer C is incorrect. Technician B is incorrect.
Answer D is incorrect. Technician A is correct.
Question 4
2
, On a straight truck equipped with air brakes, the secondary tank pressure gauge falls to
zero when she wet air tank is drained. Technician A says the one-way check valve may be
faulty.
Technician B says the foor valve may be faulty. Who is correct?
A. A only
B. B only
C. Both A and B
D. Neither A nor B
CORRECT ANSWER
Answer A is correct. The one way check valve should protect the secondary tank. The check
valve is leaking.
Answer B is incorrect. The foot valve does not separate the wet and secondary tanks.
Answer C is incorrect. Technician B is incorrect.
Answer D is incorrect. Technician A is correct.
Question 5
Which of the following could set an antilock braking system (ABS) wheel speed sensor
code:
A. Faulty modulator hold solenoid
B. Faulty modulator release solenoid
C. Incorrect wheel bearing adjustment
D. Incorrect brake adjustment
CORRECT ANSWER
Answer A is incorrect. A faulty solenoid would not cause a wheel speed sensor code. It could
cause a modulator valve code.
Answer B is incorrect. A faulty solenoid would not cause a wheel speed sensor code. It could
cause a modulator valve code
Answer C is correct. A loose wheel bearing adjustment can cause a faulty wheel speed
sensor and a wheel speed sensor code.
3
ANSWERS|BRAND NEW 2026-2027
UPDATE|GRADED A+
Question 1
Which of the following could cause the brakes on a truck to wear too fast?
A. Glazed Drums
B. Wrong linings installed
C. Low air pressure in the service tanks
D. Governor cut-out pressure too high
CORRECT ANSWER
Answer A is incorrect. Glazed drum linings are hard and do not wear. They also do not stop
the truck.
Answer B is correct. The wrong lining for the application may be the problem.
Answer C is incorrect. Low air pressure in the tanks would not cause brake wear. It may
cause a low amount of reserve air in case of multiple brake applications.
Answer D is incorrect. High governor cut=out pressure may cause the safety valve to open,
but would not cause the brakes to wear too fast.
Question 2
Which of the following could case one brake on a truck to wear faster than the others?
A. Mismatched service brake chambers
B. Mismatched parking brake chambers
C. Low air pressure in the service tanks
D. Governor cut-out pressure too low
CORRECT ANSWER
1
,Answer A is correct. Mismatched brake service chambers would apply unequal brake
application pressure from side to side, which would cause one brake to wear faster.
Answer B is incorrect. Mismatched parking brake chambers would not cause brake wear. It
would possibly allow the brake to roll when parked, because one side could have insufficient
parking brake application.
Answer C is incorrect. Low air pressure in the tanks would not cause brake wear. It may
cause a low amount of reserve air in case of multiple brake applications
Answer D is incorrect. Low governor cut-out pressure may cause an inadequate amount of
air in reserve but would not cause the brake to wear too fast.
Question 3
There is an audible air leak from under the dash when the foot valve is applied. Technician
A says the double-check valve may be faulty. Technician B says the single-check valve may
be
faulty. Who is correct?
CORRECT ANSWER
A. A only
B. B only
C. Both A and B
D. Neither A nor B
Answer A is correct. A leaking double check valve could allow air to flow to the foot valve
and out the open exhaust
Answer B is incorrect. Single check valves are used to protect the tanks. They do not cause
an air leak when the brakes are applied.
Answer C is incorrect. Technician B is incorrect.
Answer D is incorrect. Technician A is correct.
Question 4
2
, On a straight truck equipped with air brakes, the secondary tank pressure gauge falls to
zero when she wet air tank is drained. Technician A says the one-way check valve may be
faulty.
Technician B says the foor valve may be faulty. Who is correct?
A. A only
B. B only
C. Both A and B
D. Neither A nor B
CORRECT ANSWER
Answer A is correct. The one way check valve should protect the secondary tank. The check
valve is leaking.
Answer B is incorrect. The foot valve does not separate the wet and secondary tanks.
Answer C is incorrect. Technician B is incorrect.
Answer D is incorrect. Technician A is correct.
Question 5
Which of the following could set an antilock braking system (ABS) wheel speed sensor
code:
A. Faulty modulator hold solenoid
B. Faulty modulator release solenoid
C. Incorrect wheel bearing adjustment
D. Incorrect brake adjustment
CORRECT ANSWER
Answer A is incorrect. A faulty solenoid would not cause a wheel speed sensor code. It could
cause a modulator valve code.
Answer B is incorrect. A faulty solenoid would not cause a wheel speed sensor code. It could
cause a modulator valve code
Answer C is correct. A loose wheel bearing adjustment can cause a faulty wheel speed
sensor and a wheel speed sensor code.
3
