ASE T4 BRAKES - QUESTIONS AND ANSWERS |
2026 UPDATE | 100% CORRECT.
2. The Driver Vehicle Inspection Report DVIR should be submitted :
A. according to the vehicle maintenance schedule
B. when a failure occurs
C. weekly
D. daily - ANSWERS-The correct answer is D. Federal Motor Vehicle Safety
Standards ( FMVSS ) require the driver to submit a DVIR to their motor carrier
or owner at the end of each day . The DVIR is used to identify defects or
deficiencies that would result in a mechanical breakdown or effect the safe
operation of a vehicle Once a driver submits the DVIR , a motor carrier or its
agent must investigate and repair the defect or deficiency .
3. Which of the following cannot cause a drum on an air - braked vehicle to
overheat ?
A. an over - tightened brake adjuster at that wheel
B. under - adjusted brake ( s ) elsewhere on the vehicle
C. too - high governor cut - out pressure
D. driving downhill in too high a gear. - ANSWERS-3. The correct answer is C.
The governor controls the air compressor output by unloading or cycling it . It
has no direct effect on the mechanical brake parts . While the pressure
setting is important to maintain air brake system pressure within acceptable
limits , an incorrect setting will not cause the drum on an air - braked vehicle
to overheat . All other choices given , however , will cause overheating
problems .
4. All the brakes drag on a truck with hydraulic brakes . Which of the
following could be the cause ? A. air in the hydraulic system
B. too high a vacuum supply to the power brake booster
,C. a leaking secondary cup in the master cylinder
D. no brake pedal free travel - ANSWERS-4. The correct answer is D. Only a
brake pedal with no free travel will cause all of the brakes to drag . Answer A
- air in the hydraulic system , will cause a spongy pedal , while answer B - too
high a vacuum to the power booster , won't affect brake drag at all . Answer
C , a leaking secondary cup in the master cylinder , could increase pedal
travel , but won't cause the brakes to drag .
5. Which of the following could cause a pulsating brake pedal on a truck with
hydraulic brakes ?
A. zero brake pedal free travel
B. glazed linings
C. an out - of - round brake drum
D. a frozen wheel cylinder piston. - ANSWERS-5. The correct answer is C. Of
the choices given , only an out - of - round brake drum can cause pulsation in
a hydrau lic brake system . Answer A , zero brake pedal free travel , will
cause a dragging brake condition , but not pulsation . Answer B , glazed
linings , will affect stopping performance and noise , and answer D , a frozen
wheel cylinder , will de grade stopping performance , but will not cause
pulsation.
6. Air pressure gauges change an air pressure signal into an electronic
voltage signal using which of the following components ?
A. inductor
B. capacitor
C. transducer
D. regulator - ANSWERS-6. The correct answer is C. An element inside an air
pressure transducer responds to air pressure increase or decrease, and the
transducer converts that pressure differentiation into a voltage signal, which
is displayed in a proportionate reading on the dash gauge.
, 7. Technician A says that linings worn too thin on an air - braked vehicle can
cause the S - camshaft to roll over . Technician B says this condition can
cause excess brake pedal travel . Who is right ?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B - ANSWERS-7. The correct answer is A. The brake adjuster
is connected to a shaft that runs perpendicular to the plane formed by the
pushrod and slack adjuster. As the pushrod is extended, the shaft rotates.
The shaft, in turn, is connected to an S-shaped cam between the brake
shoes. As the shaft rotates, so does the cam. The brake shoes are forced
apart and against the brake drum, creating the friction needed to slow the
vehicle. Thin brake linings can allow the S-cam to roll over, but will not affect
brake pedal travel.
8. Spring brakes on an air - braked vehicle must be able to hold the vehicle
facing uphill or downhill on what percent grade ?
A. 10 %
B. 20 %
C. 30 %
D. 40 % - ANSWERS-8. The correct answer is B. Per Federal Motor Vehicle
Safety Standard (FMVSS) 121, the parking brakes must be able to hold a
vehicle, loaded to its gross weight rating, stationary on a smooth, dry,
concrete roadway, facing uphill or downhill on a 20% grade. In the
emergency mode, the parking brakes must be able to exert a retarding force
equal to 28% of the gross axle rating.
9. The driver of a truck with hydraulic brakes says the pedal reserve is too
low . Technician A says the brakes could be out of adjustment Technician B
says one brake system may have failed . Who is right ?
A. Technician A only
B. Technician B only
2026 UPDATE | 100% CORRECT.
2. The Driver Vehicle Inspection Report DVIR should be submitted :
A. according to the vehicle maintenance schedule
B. when a failure occurs
C. weekly
D. daily - ANSWERS-The correct answer is D. Federal Motor Vehicle Safety
Standards ( FMVSS ) require the driver to submit a DVIR to their motor carrier
or owner at the end of each day . The DVIR is used to identify defects or
deficiencies that would result in a mechanical breakdown or effect the safe
operation of a vehicle Once a driver submits the DVIR , a motor carrier or its
agent must investigate and repair the defect or deficiency .
3. Which of the following cannot cause a drum on an air - braked vehicle to
overheat ?
A. an over - tightened brake adjuster at that wheel
B. under - adjusted brake ( s ) elsewhere on the vehicle
C. too - high governor cut - out pressure
D. driving downhill in too high a gear. - ANSWERS-3. The correct answer is C.
The governor controls the air compressor output by unloading or cycling it . It
has no direct effect on the mechanical brake parts . While the pressure
setting is important to maintain air brake system pressure within acceptable
limits , an incorrect setting will not cause the drum on an air - braked vehicle
to overheat . All other choices given , however , will cause overheating
problems .
4. All the brakes drag on a truck with hydraulic brakes . Which of the
following could be the cause ? A. air in the hydraulic system
B. too high a vacuum supply to the power brake booster
,C. a leaking secondary cup in the master cylinder
D. no brake pedal free travel - ANSWERS-4. The correct answer is D. Only a
brake pedal with no free travel will cause all of the brakes to drag . Answer A
- air in the hydraulic system , will cause a spongy pedal , while answer B - too
high a vacuum to the power booster , won't affect brake drag at all . Answer
C , a leaking secondary cup in the master cylinder , could increase pedal
travel , but won't cause the brakes to drag .
5. Which of the following could cause a pulsating brake pedal on a truck with
hydraulic brakes ?
A. zero brake pedal free travel
B. glazed linings
C. an out - of - round brake drum
D. a frozen wheel cylinder piston. - ANSWERS-5. The correct answer is C. Of
the choices given , only an out - of - round brake drum can cause pulsation in
a hydrau lic brake system . Answer A , zero brake pedal free travel , will
cause a dragging brake condition , but not pulsation . Answer B , glazed
linings , will affect stopping performance and noise , and answer D , a frozen
wheel cylinder , will de grade stopping performance , but will not cause
pulsation.
6. Air pressure gauges change an air pressure signal into an electronic
voltage signal using which of the following components ?
A. inductor
B. capacitor
C. transducer
D. regulator - ANSWERS-6. The correct answer is C. An element inside an air
pressure transducer responds to air pressure increase or decrease, and the
transducer converts that pressure differentiation into a voltage signal, which
is displayed in a proportionate reading on the dash gauge.
, 7. Technician A says that linings worn too thin on an air - braked vehicle can
cause the S - camshaft to roll over . Technician B says this condition can
cause excess brake pedal travel . Who is right ?
A. Technician A only
B. Technician B only
C. Both A and B
D. Neither A or B - ANSWERS-7. The correct answer is A. The brake adjuster
is connected to a shaft that runs perpendicular to the plane formed by the
pushrod and slack adjuster. As the pushrod is extended, the shaft rotates.
The shaft, in turn, is connected to an S-shaped cam between the brake
shoes. As the shaft rotates, so does the cam. The brake shoes are forced
apart and against the brake drum, creating the friction needed to slow the
vehicle. Thin brake linings can allow the S-cam to roll over, but will not affect
brake pedal travel.
8. Spring brakes on an air - braked vehicle must be able to hold the vehicle
facing uphill or downhill on what percent grade ?
A. 10 %
B. 20 %
C. 30 %
D. 40 % - ANSWERS-8. The correct answer is B. Per Federal Motor Vehicle
Safety Standard (FMVSS) 121, the parking brakes must be able to hold a
vehicle, loaded to its gross weight rating, stationary on a smooth, dry,
concrete roadway, facing uphill or downhill on a 20% grade. In the
emergency mode, the parking brakes must be able to exert a retarding force
equal to 28% of the gross axle rating.
9. The driver of a truck with hydraulic brakes says the pedal reserve is too
low . Technician A says the brakes could be out of adjustment Technician B
says one brake system may have failed . Who is right ?
A. Technician A only
B. Technician B only
