Suspension

Front 1

Name the two basic styles of wheels used on heavy equipment.

Back 1

Spoke wheels and disc wheels

Front 2

Explain the main differences between the 2 wheel styles spoke and disc

Back 2

Spoke wheels are supported by bearings and can be considered as a type of hub. Disk wheels are fastened to a hub.

Front 3

Identify 2 types of disk wheels in terms of how they are piloted.

Back 3

Stud piloted is centered by the stud and nut. Hub piloted Is is centered by machine hub pads.

Front 4

If when dual tires and wheels or rims are used a spacer must be used explain the purpose of that spacer

Back 4

The spacer ensures that 2 wheels are separated significantly to prevent contact during normal operation.

Front 5

It is permissible to use any style of wheel nut when mounting stud piloted wheels

Back 5

False-only use cone/ball type tapered wheel nut

Front 6

It is permissible to use only stud piloted wheel and one hub piloted wheel as a dual wheel set

Back 6

False- Only use a set of stud piloted or a set of hub piloted wheels on a dual wheel set

Front 7

Identify 2 main types of tires, In terms of air retention methods

Back 7

Tube tire and tubless tire

Front 8

Tire tread designs can be of 2 general styles. Name and explain when these styles are typically used.

Back 8

Rib- Non traction, Steering on highway, Trailers.

Lug or block- Traction applications, drive axle.

Front 9

Explain the 2 major types of tire construction in common use.

Back 9

Bias ply- Angled cords(plies) built up into layers

Radial ply- Steel plies at 90ﾟ to beads, With steel reinforcing belts on the tread circumference.

Front 10

Tires are matched by checking the size on the sidewall of the tires

Back 10

False- A tire must be measured for circumference and diameter and be matched within allowed limits.

Front 11

Identify the equipment that could be used to measure tires in the process of matching them together

Back 11

Tape measurer, Large square or matching stick large caliber, A tire straight edge or a length of string held tightly across all tires.

Front 12

The main advantage of using a deck trailer to carry cargo is

Back 12

Easy access for loading and unloading

Front 13

Trailers that protect the load from environmental conditions are called

Back 13

Van trailers

Front 14

Trailer ground pressure is a measure of

Back 14

The amount of force created by The combined weight of the vehicle and the load divided by the area of contact between the vehicles tires and the road surface

Front 15

The unit that takes some of the weight off the trailer when oversized loads are being hauled is called a

Back 15

Jeep

Front 16

The device that connects the following trailer to the lead trailer by 2 or more Pintle hooks, couples, and drawbars is called a

Back 16

C train Dolly

Front 17

On A train combination with 2 semi trailers the following semi trailer is connected to the Lead trailer by

Back 17

Converter Dolly

Front 18

Let's 3 functions of a vehicle frame

Back 18

Platform to which all vehicle components are attached.

Support loads a vehicle intends to carry.

Handle shock and Tortional loads that act upon it when vehicle is in operation.

Front 19

Which one of the following is not a common frame rail shape

Back 19

Trapezoid.

Front 20

Define the term yield strength as it applies to the strength of a frame materials

Back 20

Yield strength refers to the maximum amount of stress that the materials can withstand without being permanently deformed.

Front 21

The term section modulus refers to the strength of frame components based on

Back 21

height

width

Thickness

shape

Front 22

List 4 functions of a vehicle suspension system

Back 22

1Secure the axle to frame well maintaining drive train components and reduce tire wear

2support weight of vehicle and cargo maintain lateral stability

3Cushion shock loads

4Allow axle to move up-and-down Relative to vertical frame so tires follow contour of road Surface.

Front 23

The suspension system must hold the axle in alignment with the frame this means that that the

Back 23

Wheels are held parallel to the frame rails

Front 24

Solid mount suspension systems are best suited to applications that

Back 24

Operate on rigid terrain

Front 25

Axles are stabilized against breaking and acceleration forced by

Back 25

Longitudial torque rods

Front 26

The function of transverse torque rods is to

Back 26

To provide side to side stability by connecting the frame rail to Axel housing

Front 27

Spring satchel accommodates challenges in Spring length as the Suspension jounces and rebounds.

Back 27

True

Front 28

The function of vertical drive pins on a rubber cushion type suspension is too

Back 28

Allow the saddle to move up-and-down as the load cushions deflect Thus maintaining alignment of saddle with frame rail.

Front 29

An advantage that that the air Springs suspension have over other suspension types is that they provide superior

Back 29

Ride quality

Front 30

The right height control valve supplies air to the air Springs when

Back 30

Additional load is added to the vehicle

Front 31

The difference between frame sag and bow is

Back 31

A sagged frame is bent downwards while a bowed frame is bent upwards.

Front 32

Corrosion of a frame material can be a result of

Back 32

climatic conditions(rain,snow ambient temperatures)

Exposure to certain cargo materials

Contact between two dissimilar metals such as aluminum and steel

Front 33

Improper frame alignment can be a source of tracking an alignment problems

Back 33

True

Front 34

2 reasons for using hardened washers on Is bolted Is frame connections are

Back 34

To prevent the head of the bolt and the nut from In bedding into the attached part or frame rail

To help distribute the load preventing localized over steering of frame parts.

Front 35

Heat treated frame rails must be heated in order to straighten them

Back 35

False

Front 36

A vehicle equipped with a leaf Spring suspension is leaning to one side a possible cause of this fault is

Back 36

Broken lead Spring

Front 37

State the procedure for checking shock absorber operation

Back 37

Remove the lower shock mount and then pull the shock piston rod out and push it in 4 to 5 times. You should feel resistance To the shock absorber movement in both directions but greater Resistance when the piston rod is pulled out.

Front 38

Equalizer beam and bushing clearance can be checked by

Back 38

Jacking the beam end up with a hydraulic Jack and checking beam and movement.

Front 39

Best way to remove equalizer beam and center bushing is to

Back 39

Use appropriate presses and/or pullers

Front 40

The difference between bar pin and other types of equalizer beam and bushing is that

Back 40

They provide a point of axle alignment adjustment.

Front 41

Rubber load cushions have a durometer number that indicates.

Back 41

The hardness of the rubber cushion which determines its load capacity

Front 42

When the load is removed from a vehicle equipped with air Springs suspension the ride height control Valve will

Back 42

Exhaust air from the air Springs until correct right height is reached

Front 43

All bearings are designed to provide support 2 moving parts keep parts in alignment increase friction and provide a replaceable Ware surface

Back 43

False

Front 44

Crush is a term used to describe the

Back 44

Radial pressure exerted on the bore

Front 45

Plane roller bearings are designed to support radial loads only

Back 45

True

Front 46

Which term best describes static seals

Back 46

They seal between non moving parts

Front 47

Which sentence best describes gaskets

Back 47

Metal gaskets can usually withstand high pressure and temperatures

Front 48

Silicone may be used with cork or paper gaskets

Back 48

False- Do not use silicone with cork or paper gaskets as the gaskets may slip out or become too thick

Front 49

Choose the answer that best relates to preload

Back 49

Free load is set by shims spacers or a Threaded ring

Front 50

Brinelling is

Back 50

Is indentation from shock loading

Front 51

With regards to bearings arcing is a term used to describe

Back 51

Marks on the bearing due to discharge of Electricity within the Baron

Front 52

Bearing failure is most often attributed too

Back 52

Contamination ingested from external sources

Front 53

When removing bearings from a shaft using the non destructive method

Back 53

Pull on the outer portion of the bearing only

Front 54

When heating bearings do not use

Back 54

Flame

Front 55

Bearings should not be heated above

Back 55

250 Celsius or 480 Fahrenheit

Front 56

2 common types of landing gears are

Back 56

Drop leg and gear operated landing gear

Front 57

When a gear operated landing gear is operated in low speed crunch shift speed is What through gears before being applied Is in a lift screw

Back 57

Reduced

Front 58

Lifting and lowering the trailer must be done with the landing gear in high speed

Back 58

False- Lifting and lowering must be done on low speed to prevent damage to the gear set

Front 59

The gears in a landing gear are lubricated

Back 59

Greece

Front 60

Which of the following vehicles does not require yearly commercial vehicle inspection

Back 60

Farm vehicles

Front 61

If a vehicle fails to meet inspection standards then spectacian mechanic must

Back 61

Refuse to issue an inspection certification

And notify the owner of the vehicle that it has failed inspection

Front 62

An inspection mechanic assumes a legal responsibility for the condition of a vehicle once he slashed she issues an inspection Certificate and attaches the insurance Decal

Back 62

True

Front 63

List the 6 major areas of a commercial vehicle that must be inspected

Back 63

Couplings and hitches

Suspension

Tires and wheels

Brakes

Lamps and electrical system

Body

Front 64

In order to pass an inspection tire pressure must be

Back 64

Within specification listed on the tireside wall

Within 10% of tires on the same axle

Front 65

Corrosion is accelerated whenever 2 dissimilar metals are in contact

Back 65

True

Front 66

Breakdown maintenance is a system of maintaining a machines whereby components and replace on a regular scheduled service interval

Back 66

False- Breakdown maintenance refers 1st to the policy of running a component on machine until something breaks at the time replacement occurs.

Front 67

Component failure and damage can be classed as primary and secondary explain what effect secondary damage may have on a machine

Back 67

Econdary damage could raise the cost of the primary components failure considerably

Numerous sub assemblies may be damaged because of the primary failure

The Extensive damage could increase the amount of time the machine is down for repair

Front 68

Off road machines are often shut down for maintenance after so many hours of operation

Back 68

True

Front 69

A regular scheduled oil analysis program does not help you predict component problems long before failure occurs

Back 69

False- An oil analysis program can definitely assist you in predicting component failure.

Front 70

A predictive maintenance system where components are replaced at regularly Scheduled service intervals have several advantages. Identify 4 advantages of this type of Predictive maintenance system.

Back 70

Increase productivity

Reduced emergency and break down time

Aids in schedule the maintenance

Reduces maintenance cost

Front 71

Trailer air and electrical connections can be made up after the trailer is securely coupled to the 5th wheel

Back 71

False

Front 72

The 1st step in uncoupling a tractor/semi trailer combination is to

Back 72

Position the unit on firm level ground

Front 73

The amount of wear in 5th wheel oscillating pins And bushings can be checked by

Back 73

Bareling the top plate up-and-down as well as back-and-forth

Front 74

A distorted or cracked 5th wheel top plate must be straightened or welded before it can be rebuilt

Back 74

False

Front 75

The contact service on a 5th wheel top plate is liberated with

Back 75

Water resistant lithium based grease

Front 76

A trailer kingpin must be replaced if it is bent more than 1ﾟ

Back 76

True

Front 77

If wheel couplings are used to connect a semi trailer 2

Back 77

A tractor

converter Dolly

The lead trailer of a b train combination

Front 78

Purpose of a coupling jaw in a 5th wheel is to engage and secure the tractor kingpin

Back 78

True

Front 79

Which of the following 5th wheels is most commonly used with

Back 79

Semi-oscillating type

Front 80

The function of the safety restraints on a trailer unit coupled with a pencil hitch is too

Back 80

Ensured that the trailer remains attached to the towing unit in the event of a trailer hitch separation