Question 1

What is a transducer?

Accepted Answer

A transducer is a device that changes mechanical or hydraulic input into an electrical signal. The mechanical transducer used to test for imbalance has a magnet that is spring loaded on both sides. It moves back and forth in a coil of wire, sending a signal to a meter in response to vibration.

Question 2

How would you test for a first order vibration?

Accepted Answer

To test for a first order vibration, raise the vehicle in the air and run the engine in gear to check the driveline. Move the vibration analyzer pickup to different places and try to determine where the energy from the vibration is located. If there is no vibration without a load on the tires, this is not a balance problem and is probably related to misalignment of parts.

Question 3

An intense vibration has more amplitude.

Accepted Answer

A) True 
 B)False  True

Question 4

____ measures vibration intensity.

Accepted Answer

A)  Hertz 
B)  Amplitude 
C)  Vibration 
D)  Frequency 
A)  Hertz 
B)  Amplitude 
C)  Vibration 
D)  Frequency

Question 5

____________________ is a combination of amplitude and frequency.

Accepted Answer

The answer of ____________________ is a combination of amplitude and...

Question 6

Shake is often caused by a vibration in the exhaust system or an engine accessory like the air-conditioning compressor.

Accepted Answer

A) True 
 B)False

Question 7

The term MOST-Likely used to describe the frequency with which a body vibrates is:

Accepted Answer

A)  amplitude 
B)  vibration 
C)  whine 
D)  resonant 
A)  amplitude 
B)  vibration 
C)  whine 
D)  resonant

Question 8

____________________ describes a part that is in motion in waves, or cycles.

Accepted Answer

The answer of ____________________ describes a part that is in...

Question 9

What is a working angle?

Accepted Answer

The working angle is the diffe

Question 10

While having a discussion, Technician A says that launch shudder occurs on acceleration from a standing start and continues until about 25 mph before it disappears. Technician B says that first order vibration occurs on acceleration from a standing start to about 25 mph before disappearing. Who is correct?

Accepted Answer

A)  A only 
B)  B only 
C)  Both A and B 
D)  Neither A nor B 
A)  A only 
B)  B only 
C)  Both A and B 
D)  Neither A nor B

Question 11

How would you check the drive shaft balance without special instruments?

Accepted Answer

First, put four numbers around the circu

Question 12

Tire and wheel imbalance is the most common cause of vibration concerns.

Accepted Answer

A) True 
 B)False

Question 13

An automotive suspension system has a natural frequency in the range of 10 to 15 Hz.

Accepted Answer

A) True 
 B)False

Question 14

The severity, or amplitude, of a vibration will be greatest at its ____________________.

Accepted Answer

The answer of The severity, or amplitude, of a vibration...

Question 15

All of the following statements are true EXCEPT:

Accepted Answer

A)  drive shafts can be aluminum, steel, carbon fiber bonded to aluminum yokes, or composite that is pultruded over an aluminum tube. 
B)  most steel drive shafts are shorter than 60" to 65". 
C)  short steel shafts use a center support bearing. 
D)  aluminum drive shafts can be 85" to 90" because aluminum has a higher "critical speed." 
A)  drive shafts can be aluminum, steel, carbon fiber bonded to aluminum yokes, or composite that is pultruded over an aluminum tube. 
B)  most steel drive shafts are shorter than 60" to 65". 
C)  short steel shafts use a center support bearing. 
D)  aluminum drive shafts can be 85" to 90" because aluminum has a higher "critical speed."

Question 16

All of the following statements are true EXCEPT:

Accepted Answer

A)  an EVA has the capability of freezing an event. 
B)  a snapshot has five frames. 
C)  shake is a low-frequency vibration of 5 to 20 Hz. 
D)  roughness is a higher frequency vibration than shake. 
A)  an EVA has the capability of freezing an event. 
B)  a snapshot has five frames. 
C)  shake is a low-frequency vibration of 5 to 20 Hz. 
D)  roughness is a higher frequency vibration than shake.

Question 17

Which of the following statements is LEAST-Likely true?

Accepted Answer

A)  A part with runout should be balanced if it causes parts to bind up once per revolution. 
B)  Engine accessory brackets have been designed to excite at 400 Hz or higher. 
C)  The engine, torque converter, and driveshaft change in frequency as rpm changes. 
D)  Driveshafts are balanced on the ends, not in the middle. 
A)  A part with runout should be balanced if it causes parts to bind up once per revolution. 
B)  Engine accessory brackets have been designed to excite at 400 Hz or higher. 
C)  The engine, torque converter, and driveshaft change in frequency as rpm changes. 
D)  Driveshafts are balanced on the ends, not in the middle.

Question 18

____________________ is the number of cycles that take place during a period of time.

Accepted Answer

The answer of ____________________ is the number of cycles that...

Question 19

A ____ occurs when one vibration interacts with another.

Accepted Answer

A)  beat/boom vibration 
B)  first order vibration 
C)  second order vibration 
D)  snapshot 
A)  beat/boom vibration 
B)  first order vibration 
C)  second order vibration 
D)  snapshot

Question 20

While having a discussion, Technician A says that to extend U-joint service life, the angle of the transmission output shaft and the front of the differential should be within 2 degrees of each other. Technician B says that the differential should be within 1/2 degree of each other. Who is correct?

Accepted Answer

A)  A only 
B)  B only 
C)  Both A and B 
D)  Neither A nor B 
A)  A only 
B)  B only 
C)  Both A and B 
D)  Neither A nor B

Exam 79: Driveline Vibration

What is a transducer?

How would you test for a first order vibration?

An intense vibration has more amplitude.

____ measures vibration intensity.

____________________ is a combination of amplitude and frequency.

Shake is often caused by a vibration in the exhaust system or an engine accessory like the air-conditioning compressor.

The term MOST-Likely used to describe the frequency with which a body vibrates is:

____________________ describes a part that is in motion in waves, or cycles.

What is a working angle?

How would you check the drive shaft balance without special instruments?

Tire and wheel imbalance is the most common cause of vibration concerns.

An automotive suspension system has a natural frequency in the range of 10 to 15 Hz.

The severity, or amplitude, of a vibration will be greatest at its ____________________.

All of the following statements are true EXCEPT:

All of the following statements are true EXCEPT:

Which of the following statements is LEAST-Likely true?

____________________ is the number of cycles that take place during a period of time.

A ____ occurs when one vibration interacts with another.

While having a discussion, Technician A says that to extend U-joint service life, the angle of the transmission output shaft and the front of the differential should be within 2 degrees of each other. Technician B says that the differential should be within 1/2 degree of each other. Who is correct?

Introduction to the Automobile

Automotive Careers and Technician Certification

Shop Safety

Shop Management, Service Records, and Parts

Locating Service Information and Specifications

Measuring Tools and Systems

Hardware, Fasteners, Drills, and Thread Repair

Shop Tools

General Shop Equipment

Cleaning Equipment and Methods

Lifting Equipment and Air Compressors

Engine Lubrication

Underhood and Body Inspection Car on Ground

Undercar Inspection and Service

Introduction to the Engine

Engine Classifications and Advanced Transportation Technologies

Engine Size and Measurements

Engine Upper End

Engine Lower End and Lubrication System Theory

Cooling System Theory

Cooling System Service

Automotive Belts

Automotive Hoses

Automotive Plumbing: Tubing and Pipe

Basic Electrical System Theory and Repairs

Battery Fundamentals

Battery Service

Starting System Fundamentals

Starting System Service

Charging System Fundamentals

Charging System Service

Lighting and Wiring Fundamentals

Lighting and Wiring Service

Safety, Security, Comfort Systems, and Electrical Accessories

Heating and Air Conditioning Fundamentals

Heating and Air Conditioning Service

Ignition System Fundamentals

Ignition System Service

Fuels and Alternative Fuels

Fuel System Fundamentals

Fuel System Service

Intake and Exhaust Systems, Turbochargers and Superchargers

Emission Control System Fundamentals

Emission Control System Service

Electronics and Computer Systems Fundamentals

Electronics and Computer Systems Service

Advanced Emissions and On-Board Diagnostics Odb

Diagnosing Engine Performance Problems

Diagnosing Engine Mechanical Problems

Engine Removal and Disassembly

Engine Sealing, Gaskets, Fastener Torque

Engine Diagnosis and Service: Cylinder Head and Valvetrain

Engine Diagnosis and Service: Block, Crankshaft, Bearings, and Lubrication System

Engine Diagnosis and Service: Piston, Piston Rings, Connecting Rod, Engine Balancing

Ordering Parts, Short and Long Blocks, Engine Assembly

Engine Installation, Break In, and In-Chassis Repairs

Brake Fundamentals

Brakes Service

Anti-Lock Brakes Traction and Stability Control

Bearings, Seals, and Greases