Crucial Transmission Points

Question 1

What would excessive free play in the clutch cause?

Answer 1

Clutch drag

Question 2

What would insufficient free play in the clutch cause?

Answer 2

Clutch slip

Question 3

What is the most likely fault if the clutch emits a constant bearing whine, when the clutch is not depressed?

Answer 3

A worn clutch release bearing

Question 4

Which of the following components is not part of the clutch release mechanism:
Clutch pedal
Pressure plate
Clutch cable
Centre plate

Answer 4

Centre plate

Question 5

What is the purpose of the sliding joint fitted to as prop shaft?

Answer 5

To accomodate for changes in the propellor shaft length due to movement

Question 6

Why is a customer’s signature required to authorise work being carried out on a vehicle?

Answer 6

It creates a legally binding contract between the customer and the garage

Question 7

What type of gears are used in a sliding mesh gearbox?

Answer 7

Spur gears

Question 8

Which fault can cause clutch slip?

Answer 8

Lack of free play

Question 9

What should be done to safeguard yourself and others when working in a vehicle repair workshop?

Answer 9

Adhere to all the above

Question 10

Why are multi-plate clutches used

Answer 10

When there is not much space and a high torque needs to be transmitted

Question 11

Which of the following is not a legal requirement when test-driving a vehicle on a public road:
A current road fund license
Driver wearing a seat belt
Trade plates front and rear
A valid driver’s license

Answer 11

Trade plates front and rear

Question 12

Why should you report any defects when carrying out a routine service on a vehicle?

Answer 12

So the customer can be contacted to get their authority to do extra work

Question 13

What is the most likely cause of difficulty engaging gears, especially in 1st?

Answer 13

Clutch drag

Question 14

What can a misaligned propeller shaft in a rear wheel drive car cause?

Answer 14

Transmission vibration

Question 15

An automatic gearbox usually contains a…

Answer 15

Sun gear, planet gear and annulus/ring gear

Question 16

What dooes a front wheel drive transmission use?

Answer 16

Constant velocity joints

Question 17

List 5 components of the clutch release mechanism

Answer 17

Master cylinder, slave cylinder, hydraulic lines, clutch pedal, clutch fork

Question 18

What would the effect of air in the clutch hydraulic operating system be?

Answer 18

The clutch being unable to fully disengage, because hydraulic transmission relies on compression of liquid and air can be compressed, reducing pressure

Question 19

Give a symptom of clutch slip

Answer 19

Revs increase bu the car does not accelerate

Question 20

Give a symptom of clutch drag

Answer 20

Difficulty shifting gears

Question 21

Give a symptom of clutch judder

Answer 21

Jarring vibration in the steering wheel

Question 22

Name the clutch component that drives the gearbox

Answer 22

The clutch plate

Question 23

What does the clutch interlock mechanism do?

Answer 23

Prevents 2 gears from being selected simultaneously

Question 24

How are gears connected to the output shaft on a 4-speed constant mesh gearbox?

Answer 24

Using needle roller bearings

Question 25

What will a worn synchro cone/baulk ring result in?

Answer 25

Crashing into gear

Question 26

Define hypoid axle

Answer 26

A kind of rear axle where the pinion engages the crown wheel below the centre line

Question 27

What would a typical final drive ratio be?

Answer 27

Between 3:1 and 4:1

Question 28

Where can a fully floating axle be found?

Answer 28

On light HGVs

Question 29

In a vehicle with a fully floating rear axle, what will a broken axle cause?

Answer 29

The wheel will not fall off

Question 30

List 3 advantages of using a diaphragm spring clutch over a multi coil spring clutch

Answer 30

Smaller in size and weight, transfers more torque, higher load-carrying capacity

Question 31

List 2 reasons to use a clutch centre plate with a spring hub

Answer 31

Reduces torsional stress, absorbs shock loads from sudden clutch engagement

Question 32

What is the difference of the transmission ratios in a rear wheel drive car, compared to front wheel drive?

Answer 32

There is only one transmission ratio, because it's just input to output shaft, no lay shaft

Question 33

Why does the baulk ring/synchro cone have a screw type finish on its surface?

Answer 33

To let oil escape

Question 34

What kind of oil should be used in a rear wheel drive final assembly?

Answer 34

EP (extreme pressure) oil

Question 35

What substance is used to lubricate the wheel bearings in a car?

Answer 35

LM grease (might just say grease)

Question 36

The gear ratio is 2:1. If the engine sends 120 Nm of torque at 5000 rpm into the input shaft, what will the gearbox send into the output shaft?

Answer 36

240 Nm at 2500 rpm

Question 37

Where does the half shaft transmit drive from?

Answer 37

Propellor shaft to the gearbox universal joints

Question 38

The clutch fork actuator system may be a direct mechanical system or...

Answer 38

Hydraulic

Question 39

When calculating the gear ratio on a gear set that incorporates the idler gear...

Answer 39

Ignore the idler gear size, focus on driver and driven

Question 40

What's another term for gear reduction?

Answer 40

Underdrive

Question 41

How does a coil spring clutch look different do a diaphragm spring clutch?

Answer 41

The springs come outward

Question 42

The gear ratio is 2:1. What will happen?

Answer 42

Torque will be double the input. Speed will be half the input

Question 43

A better term for longituadinal driveline?

Answer 43

Transverse

Question 44

What tool do you use to remove the inner track of a bearing?

Answer 44

Puller

Question 45

What's the prop shaft made of?

Answer 45

Steel

Question 46

What vehicle will a fully floating axle be used on?

Answer 46

Light HGVs

Question 47

Which 2 transmission components are inspected in an MOT test?

Answer 47

The CV joint and boot

Question 48

Why would you use a DTI on a final drive assembly?

Answer 48

To check backlash

Question 49

When is clutch drag more noticeable?

Answer 49

In 1st and reverse gear

Question 50

What does the detent do?

Answer 50

Holds the selector shaft in place

Question 51

Which clutch component drives the gearbox?

Answer 51

Clutch plate

Question 52

Name one symptom of clutch slip

Answer 52

Revs go up, without accelerating

Question 53

A visual inspection of the clutch release assembly will reveal...

Answer 53

Surface cracks and hotspots

Question 54

What is the purpose of the synchronisers?

Answer 54

Ensure that the gears rotate at the same speed, to prevent gear clash

Question 55

What fault is most likely to produce clutch judder?

Answer 55

Sticking clutch cable

Question 56

What is the most likely cause of a load knocking sound while turning in front-wheel drive?

Answer 56

A badly worn constant velocity joint

Question 57

What can a badly worn gear change mechanism result in?

Answer 57

Difficulty changing gears

Question 58

What will a rear crankshaft oil seal leaking result in?

Answer 58

Clutch slip

Question 59

Which of these will result in failing an MOT test:

Answer 59

An outer constant velocity joint gaiter is split

Question 60

What happens if the interlock mechanism is defective?

Answer 60

Transmission would lock up, causing damage