Page 1 of 41
310T Practice Exam 2, 136 Q&A, Complete
Practice Exam Material A+ Score
Introduction
This document contains 136 practice questions and precise answers
for the 310T truck and coach technician exam. It covers air brakes,
electrical systems, HVAC and refrigeration, steering and suspension,
frame and body repairs, diesel engines, fuel and emissions systems,
transmissions, differentials, and hydraulics. The material is
designed as comprehensive exam preparation with answer
selections provided for each question.
Exam Questions and Answers
What safety precautions must be followed when working on
pressurized air brake components?!
Always wear safety glasses and drain air pressure before
dismantling components
Not to worry, pressurized air is not dangerous
Draining air pressure is not required before dismantling
components
Air pressure in a brake system is contained and cannot leak out
when dismantled --- correct precise answer ---Always wear safety
glasses and drain air pressure before dismantling components
In a B-train combination which of the following relay valves would
likely have the lowest crack pressure?!
The front tractor axle
,Page 2 of 41
The rear drive axle
The pup axle
The lead trailer axle --- correct precise answer ---The pup axle
Which of the following would be an output of the ECU (electronic
control unit) of an air brake ABS (anti-lock brake system)?!
The ABS indicator dash light
The exciter ring
The brake treadle valve
The speed sensor --- correct precise answer ---The ABS indicator
dash light
Brake wear is uneven on only one side of the shoes. What should be
checked?!
Anchor pins and bushings
Improper sized shoes
Worn S-cam bushings
ABS sensor out of adjustment --- correct precise answer ---Anchor
pins and bushings
What is the desired air gap between the ABS wheel speed sensor
and the exciter ring?!
1/4" (6.25mm)
3/8" (9.5mm)
Air gap is not critical
As close as possible --- correct precise answer ---As close as
possible
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What is the proper position of hole(s) on air spring brake
chambers?!
At a 90° angle
At a 30° angle
Facing downwards, toward the road
On the top, where it can be accessed --- correct precise answer ---
Facing downwards, toward the road
What is the purpose of residual pressure in a hydraulic brake
system
To increase speed of a brake application
To inhibit moisture infiltrating the hydraulic system
To increase applied brake pressure
To decrease applied brake pressure --- correct precise answer ---To
inhibit moisture infiltrating the hydraulic system
Air pressure is higher than normal. What is the most likely
problem?!
Un-loader valve is stuck open
Defective governor circuit
Signal from supply tank
Air compressor is over capacity --- correct precise answer ---
Defective governor circuit
What is an important requirement when selecting replacement S-
cams?!
Identify if a left or right hand S-cam is required
None, as all S-cams are identical
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Check for S-cam roller lubrication
Test Rockwell hardness --- correct precise answer ---Identify if a
left or right hand S-cam is required
What results when the dash-mounted trailer air supply valve (red)
is pulled outward (closed)?!
Air is directed through the tractor protection valve
The trailer air supply line is fully charged
The tractor parking brakes are applied
The trailer parking brakes are applied --- correct precise answer ---
The trailer parking brakes are applied
When servicing an air dryer what also requires replacement?!
Purge valve
Heater element
Desiccant filter
Governor --- correct precise answer ---Desiccant filter
When the inversion valve of an air brake vehicle is in effect, what
does it modulate to slow the vehicle?!
Holds off pressure in the spring brake chamber
Directs air pressure to the service side of the dual chamber
Releases stored air pressure from a separate reservoir
Applies hydraulic pressure to the brakes --- correct precise answer
---Holds off pressure in the spring brake chamber
What type of signal does an ABS wheel speed sensor provide?!
A digital signal
310T Practice Exam 2, 136 Q&A, Complete
Practice Exam Material A+ Score
Introduction
This document contains 136 practice questions and precise answers
for the 310T truck and coach technician exam. It covers air brakes,
electrical systems, HVAC and refrigeration, steering and suspension,
frame and body repairs, diesel engines, fuel and emissions systems,
transmissions, differentials, and hydraulics. The material is
designed as comprehensive exam preparation with answer
selections provided for each question.
Exam Questions and Answers
What safety precautions must be followed when working on
pressurized air brake components?!
Always wear safety glasses and drain air pressure before
dismantling components
Not to worry, pressurized air is not dangerous
Draining air pressure is not required before dismantling
components
Air pressure in a brake system is contained and cannot leak out
when dismantled --- correct precise answer ---Always wear safety
glasses and drain air pressure before dismantling components
In a B-train combination which of the following relay valves would
likely have the lowest crack pressure?!
The front tractor axle
,Page 2 of 41
The rear drive axle
The pup axle
The lead trailer axle --- correct precise answer ---The pup axle
Which of the following would be an output of the ECU (electronic
control unit) of an air brake ABS (anti-lock brake system)?!
The ABS indicator dash light
The exciter ring
The brake treadle valve
The speed sensor --- correct precise answer ---The ABS indicator
dash light
Brake wear is uneven on only one side of the shoes. What should be
checked?!
Anchor pins and bushings
Improper sized shoes
Worn S-cam bushings
ABS sensor out of adjustment --- correct precise answer ---Anchor
pins and bushings
What is the desired air gap between the ABS wheel speed sensor
and the exciter ring?!
1/4" (6.25mm)
3/8" (9.5mm)
Air gap is not critical
As close as possible --- correct precise answer ---As close as
possible
,Page 3 of 41
What is the proper position of hole(s) on air spring brake
chambers?!
At a 90° angle
At a 30° angle
Facing downwards, toward the road
On the top, where it can be accessed --- correct precise answer ---
Facing downwards, toward the road
What is the purpose of residual pressure in a hydraulic brake
system
To increase speed of a brake application
To inhibit moisture infiltrating the hydraulic system
To increase applied brake pressure
To decrease applied brake pressure --- correct precise answer ---To
inhibit moisture infiltrating the hydraulic system
Air pressure is higher than normal. What is the most likely
problem?!
Un-loader valve is stuck open
Defective governor circuit
Signal from supply tank
Air compressor is over capacity --- correct precise answer ---
Defective governor circuit
What is an important requirement when selecting replacement S-
cams?!
Identify if a left or right hand S-cam is required
None, as all S-cams are identical
, Page 4 of 41
Check for S-cam roller lubrication
Test Rockwell hardness --- correct precise answer ---Identify if a
left or right hand S-cam is required
What results when the dash-mounted trailer air supply valve (red)
is pulled outward (closed)?!
Air is directed through the tractor protection valve
The trailer air supply line is fully charged
The tractor parking brakes are applied
The trailer parking brakes are applied --- correct precise answer ---
The trailer parking brakes are applied
When servicing an air dryer what also requires replacement?!
Purge valve
Heater element
Desiccant filter
Governor --- correct precise answer ---Desiccant filter
When the inversion valve of an air brake vehicle is in effect, what
does it modulate to slow the vehicle?!
Holds off pressure in the spring brake chamber
Directs air pressure to the service side of the dual chamber
Releases stored air pressure from a separate reservoir
Applies hydraulic pressure to the brakes --- correct precise answer
---Holds off pressure in the spring brake chamber
What type of signal does an ABS wheel speed sensor provide?!
A digital signal
