Heavy Duty Mechanic Exam (V)
Questions and Answers Latest Version
Already Passed
What does a turbocharger primarily do in a diesel engine?
A. Reduces oil pressure
B. Increases coolant flow
✔✔C. Forces more air into the combustion chamber
D. Slows down the piston speed
Which of the following components converts mechanical energy into hydraulic pressure?
A. Actuator
✔✔B. Hydraulic pump
C. Solenoid
D. Cylinder rod
When replacing brake pads on an air disc brake system, what must be checked first?
A. Oil filter
B. Fuel line
1
,✔✔C. Rotor thickness
D. Transmission linkage
What tool is best for checking cylinder bore wear?
A. Depth gauge
✔✔B. Dial bore gauge
C. Tension wrench
D. Micrometer caliper
Which fluid is typically used in power steering systems?
A. Brake fluid
✔✔B. Hydraulic fluid
C. Engine oil
D. Coolant
What is the most likely result of a blocked DPF (diesel particulate filter)?
A. Sudden tire failure
✔✔B. Loss of engine power
2
,C. Transmission slipping
D. Fuel injector flooding
What is the purpose of a glow plug in a diesel engine?
A. Cool the combustion chamber
✔✔B. Assist in cold starting
C. Reduce engine noise
D. Circulate coolant
If a truck pulls to one side during braking, the issue is likely:
✔✔A. Uneven brake force
B. Transmission delay
C. Clutch misalignment
D. Worn tires only
What does a multimeter measure in a circuit?
✔✔A. Voltage, current, and resistance
B. Only temperature
3
, C. Only voltage
D. Engine pressure
Why is it important to torque wheel lug nuts to specification?
A. To increase fuel economy
✔✔B. To avoid brake rotor damage or wheel loss
C. To improve suspension travel
D. To cool down the tires
What is cavitation damage in an engine block often caused by?
A. Overfilled oil tank
✔✔B. Air bubbles in coolant
C. Weak spark plugs
D. Dirty fuel
In a manual transmission, the purpose of the clutch is to:
✔✔A. Disengage the engine from the drivetrain
B. Pump fuel into the cylinders
4
Questions and Answers Latest Version
Already Passed
What does a turbocharger primarily do in a diesel engine?
A. Reduces oil pressure
B. Increases coolant flow
✔✔C. Forces more air into the combustion chamber
D. Slows down the piston speed
Which of the following components converts mechanical energy into hydraulic pressure?
A. Actuator
✔✔B. Hydraulic pump
C. Solenoid
D. Cylinder rod
When replacing brake pads on an air disc brake system, what must be checked first?
A. Oil filter
B. Fuel line
1
,✔✔C. Rotor thickness
D. Transmission linkage
What tool is best for checking cylinder bore wear?
A. Depth gauge
✔✔B. Dial bore gauge
C. Tension wrench
D. Micrometer caliper
Which fluid is typically used in power steering systems?
A. Brake fluid
✔✔B. Hydraulic fluid
C. Engine oil
D. Coolant
What is the most likely result of a blocked DPF (diesel particulate filter)?
A. Sudden tire failure
✔✔B. Loss of engine power
2
,C. Transmission slipping
D. Fuel injector flooding
What is the purpose of a glow plug in a diesel engine?
A. Cool the combustion chamber
✔✔B. Assist in cold starting
C. Reduce engine noise
D. Circulate coolant
If a truck pulls to one side during braking, the issue is likely:
✔✔A. Uneven brake force
B. Transmission delay
C. Clutch misalignment
D. Worn tires only
What does a multimeter measure in a circuit?
✔✔A. Voltage, current, and resistance
B. Only temperature
3
, C. Only voltage
D. Engine pressure
Why is it important to torque wheel lug nuts to specification?
A. To increase fuel economy
✔✔B. To avoid brake rotor damage or wheel loss
C. To improve suspension travel
D. To cool down the tires
What is cavitation damage in an engine block often caused by?
A. Overfilled oil tank
✔✔B. Air bubbles in coolant
C. Weak spark plugs
D. Dirty fuel
In a manual transmission, the purpose of the clutch is to:
✔✔A. Disengage the engine from the drivetrain
B. Pump fuel into the cylinders
4
