T4 ASE BRAKES (MEDIUM/HEAVY
DUTY BRAKES) EXAM 2025/2026
The three ports on a air governor are - Reservoir unloader exhaust
Air tank pressure valve on the the tanks will open at - 150 psi
Air is leaking from the quick release valve mounted on the front axle during a service brake application -
Quick release
A truck with abs needs the abs wheel speed sensor reluctor replaced how many teeth should the new
abs wheel speed sensor have - 100 teeth
What is the the minimum brake shoe line thickness on a s-cam drum brakes - .250 inches
Tech a says that a wheel speed sensor sends a D.C. Voltage signals to the ecu tech b b says that the
frequency of ac voltage cycles is directly proportional to wheel speed who is correct - Tech b
The maximum acceptable air leak on a straight truck (parking brakes applied) is - 2 psi in one minute
The spring brakes on a truck should automatically apply when air pressure to the push-pull valve on the
dash drops to below - Between 20 and 40 so 30
A broken air compressor unloaded valve spring will most likely cause - Slow air buildup time
A compressor has a broken connecting rod the air compressor crankshaft is blue which of the following
could have caused the air compressor to fail - Restricted oil supply
, Which of the following would be the most normal end play spec for a set of tapered roller front wheel
bearing - .001 to .005 inches
When constant pressure is held on the service brake pedal on a truck with hydraulic brakes it slowly falls
to the floor there are no extrnal brake fluid leaks which of the following could be the cause - The fluid is
by-passing inside the master cylinder
An air disc brake is being measured for thickness variation tech a say two dial indicators can be used
tech b says an outside micrometer can be used who is correct - Both
Which of the following is the correct way to test the inversion valve - Drain the primary tank and watch
the action of the parking brakes
What should be used to clean abs electric connectors - Alcohol
The fitting on a truck equipped with air brakes must be stamped with - Dot
The air lines used on a truck equipped with air brakes must be stamped with - Dot
What is a duplex gauge - An example of a duplex gauge is the dual air pressure gauge found on many
trucks. It is one gauge with two needles
Tech a say the same electronic control unit (Ecu) operates The antilock braking systems (abs) on the
tractor and trailer tech b says that if replacement tires are of different size from the original tires the
wheel speed sensor are affected what is correct - Tech b
Truck with disc brakes has dragging brakes says the calipers may be sticking tech b says the master
cylinder may be passing fluid who is correct - Tech a
What is the least likely cause of trailer abs failure - A failed abs electronic control unit
DUTY BRAKES) EXAM 2025/2026
The three ports on a air governor are - Reservoir unloader exhaust
Air tank pressure valve on the the tanks will open at - 150 psi
Air is leaking from the quick release valve mounted on the front axle during a service brake application -
Quick release
A truck with abs needs the abs wheel speed sensor reluctor replaced how many teeth should the new
abs wheel speed sensor have - 100 teeth
What is the the minimum brake shoe line thickness on a s-cam drum brakes - .250 inches
Tech a says that a wheel speed sensor sends a D.C. Voltage signals to the ecu tech b b says that the
frequency of ac voltage cycles is directly proportional to wheel speed who is correct - Tech b
The maximum acceptable air leak on a straight truck (parking brakes applied) is - 2 psi in one minute
The spring brakes on a truck should automatically apply when air pressure to the push-pull valve on the
dash drops to below - Between 20 and 40 so 30
A broken air compressor unloaded valve spring will most likely cause - Slow air buildup time
A compressor has a broken connecting rod the air compressor crankshaft is blue which of the following
could have caused the air compressor to fail - Restricted oil supply
, Which of the following would be the most normal end play spec for a set of tapered roller front wheel
bearing - .001 to .005 inches
When constant pressure is held on the service brake pedal on a truck with hydraulic brakes it slowly falls
to the floor there are no extrnal brake fluid leaks which of the following could be the cause - The fluid is
by-passing inside the master cylinder
An air disc brake is being measured for thickness variation tech a say two dial indicators can be used
tech b says an outside micrometer can be used who is correct - Both
Which of the following is the correct way to test the inversion valve - Drain the primary tank and watch
the action of the parking brakes
What should be used to clean abs electric connectors - Alcohol
The fitting on a truck equipped with air brakes must be stamped with - Dot
The air lines used on a truck equipped with air brakes must be stamped with - Dot
What is a duplex gauge - An example of a duplex gauge is the dual air pressure gauge found on many
trucks. It is one gauge with two needles
Tech a say the same electronic control unit (Ecu) operates The antilock braking systems (abs) on the
tractor and trailer tech b says that if replacement tires are of different size from the original tires the
wheel speed sensor are affected what is correct - Tech b
Truck with disc brakes has dragging brakes says the calipers may be sticking tech b says the master
cylinder may be passing fluid who is correct - Tech a
What is the least likely cause of trailer abs failure - A failed abs electronic control unit
