Deck 99: Drum Brakes

Question 1

Two technicians are discussing drum brake shoes. Technician A says that forward and rear-facing shoes are the same and can be installed in either position on any drum brake system. Technician B says that the darker color linings should always be placed toward the front of the vehicle Which technician is correct?

A)Technician A only
B)Technician B only
C)Both Technicians A and B
D)Neither technician A nor B

Answer 1

Neither technician A nor B

Question 2

Two technicians are discussing brake lining edge codes. Technician A says that the code can identify the manufacturer. Technician B says that all friction material from the same manufacturer will have the same edge codes. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both Technicians A and B
D)Neither technician A nor B

Answer 2

Technician A only

Question 3

Technician A says that starwheel adjusters use different threads (left and right handed) for the left and right sides of the vehicle. Technician B says that a pawl controls the teeth of the starwheel adjuster. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both Technicians A and B
D)Neither technician A nor B

Answer 3

Both Technicians A and B

Question 4

Technician A says that drum brakes can fail to slow the vehicle if driven through deep water. Technician B says that when drum brakes get hot, the brake pedal will drop because the drum expands away from the shoes. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both Technicians A and B
D)Neither technician A nor B

Question 5

Technician A says that the anchor pin (shoe anchor) is used to hold one end of the primary and secondary shoe return springs. Technician B says that shoe anchor prevents the brake shoes from rotating with the drum when the brakes are applied. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both Technicians A and B
D)Neither technician A nor B

Question 6

Drum brake shoes ________.

A)Can have one shoe that is longer than the other on the same wheel brake
B)Can have bonded linings
C)Can have riveted linings
D)All of the above are possible

Question 7

Which lining does most of the braking on a dual-servo brake?

A)Both contribute equally
B)Front (forward facing)
C)Rear (rearward facing)
D)Depends on the speed of the vehicle

Question 8

Which lining does most of the braking on a leading/trailing brake?

A)Depends on the speed of the vehicle
B)Trailing (rearward facing)
C)Both contribute equally
D)Leading (forward facing)

Question 9

Two technicians are discussing drum brake self-adjusters. Technician A says that some brakes self-adjust when the brakes are released when the vehicle is driven in reverse. Technician B says that some brakes self-adjust when the brakes are applied rather than when released. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both Technicians A and B
D)Neither technician A nor B

Question 10

A typical drum brake backing-plate has how many shoe support pads (also called ledges)?

A)4
B)8
C)3
D)6

Question 11

A typical drum brake uses how many hold-down springs?

A)1
B)6
C)4
D)2

Question 12

The brakes on a dual-servo drum system are designated as ________.

A)Two leading shoes
B)Primary and secondary
C)Leading and trailing
D)None of the above

Question 13

On the dual-servo braking system, which shoe does most of the braking during forward movement of the vehicle?

A)The secondary shoe
B)The primary shoe
C)Both A and B
D)None of the above

Question 14

On non-servo brakes, which shoe does most of the braking in during forward movement of the vehicle?

A)The primary shoe
B)The secondary shoe
C)The leading shoe
D)The trailing shoe

Question 15

Cup expanders are used in some wheel cylinders to ________.

A)Help the cups seal against high pressure
B)Allow for wear on the cylinder walls
C)Allow for the expansion of the fluid as the temperature increases
D)Hold the lips of the cups against the cylinder walls

Question 16

Technician A says that the labyrinth seal (drum groove) helps to keep water from getting into a drum brake. Technician B says that only synthetic brake grease, lithium brake grease or anti-seize compound should be used as a brake lubricant. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both Technicians A and B
D)Neither technician A nor B

Question 17

The shoe support pads ________.

A)Hold the shoes against the drum when the parking brake is applied
B)Prevent the wheel cylinder pistons from coming out of their bores
C)Are lightly coated with silicone brake grease to minimize wear
D)Prevent the brake shoes from rotating with the drum

Question 18

Mechanical fade occurs when the friction material overheats.

Question 19

Holes may be provided in the backing plate for inspecting brake lining wear.

Question 20

Brake shoe holddowns are used to reduce brake noise.

Question 21

Trailing shoes generally wear at a faster rate than leading shoes.

Question 22

Brake drum rotation de-energizes the trailing shoe.

Question 23

A leading-trailing brake works well in reverse but not well forward.

Question 24

The dual-servo brake is more powerful than any non-servo design.

Question 25

The lining of the secondary shoe is usually larger than the primary shoe lining.

Question 26

The greatest disadvantage of drum brakes is ________.

A)Lack of power assist action
B)Brake fade
C)Poor parking brake performance
D)Brake adjustment

Question 27

Technician A says that a disadvantage of drum brakes is that they require an adjusting mechanism to maintain the proper clearance between the shoe and drum. Technician B says that a disadvantage of drum brakes is that they pull the car to one side during braking under certain conditions. Which technician is correct?

A)Technician A only
B)Technician B only
C)Both technicians A and B
D)Neither technician A nor B

Question 28

________ action uses drum rotation to force the brake shoe outward and wedge it tightly against the brake drum.

A)Self-energizing
B)Centripetal
C)Servo
D)Centrifugal

Question 29

________ action uses the stopping power of one shoe to help increase the application force of the other shoe.

A)Centrifugal
B)Servo
C)Self-energizing
D)Centripetal

Question 30

In a servo brake, the secondary shoe provides approximately what percentage of the total stopping power?

A)30
B)75
C)70
D)55

Question 31

The last two letters of a lining edge code reads EF. This means ________.

A)The lining has a higher coefficient of friction when cold than when hot
B)The lining meets SAE standards for durability
C)The lining has a higher coefficient of friction when hot than when cold
D)The lining manufacturing code

Question 32

Automatic adjusters may be actuated by all of the following EXCEPT ________.

A)Air pressure
B)Lever
C)Parking brake
D)Cable

Question 33

What term describes component "A" in this illustration?

A)Shoe anchor
B)Mounting pin
C)Shoe adjuster
D)Bleeder screw

Question 34

What term describes component "B" in this illustration?

A)Support pads
B)Shoe nibs
C)Vibration dampers
D)Shoe anchors

Question 35

Identify the parking brake strut in this illustration.

A)A
B)B
C)C
D)D

Question 36

What type of drum brake system is shown below?

A)Dual-servo
B)Double-leading
C)Leading-trailing
D)Double-trailing

Question 37

What type of drum brake system is shown below?

A)Dual-servo
B)Double-trailing
C)Double-leading
D)Leading-trailing