Deck 52: Disc Brakes

Question 1

Uneven lug nut torque can cause a pulsating brake pedal.

Answer 1

True

Question 2

A rear disc/drum parking brake uses the inside of each rear wheel hub and rotor assembly as a parking brake drum.

Answer 2

True

Question 3

The splash shield and wheel direct air over the rotor to aid cooling.

Answer 3

True

Question 4

Which of the following statements concerning brakes is NOT correct?

A) Disc brakes can handle more heat than drum brakes
B) Drum brakes resist fading better than disc brakes
C) Disc brakes automatically adjust as the pads wear
D) Disc brakes are more resistant to water fade than drum brakes

Question 5

Sliding calipers move on bolts or pins.

Question 6

A typical fixed caliper housing is designed with one caliper piston.

Question 7

What channels the flow of air over the exposed rotor surfaces?

A) webs
B) hub assembly
C) splash shield
D) caliper assembly

Question 8

A typical floating caliper housing is designed with one caliper piston.

Question 9

Electrical sensors on some vehicles advise the driver when the brake pads have worn thin and need to be replaced.

Question 10

All manufacturers recommend honing the caliper bore when overhauling the calipers.

Question 11

When replacing rear pads on actuating-type calipers, the piston must be kept from spinning as the C-clamp pushes the piston back into the caliper bore.

Question 12

When hydraulic pressure is diminished, the caliper piston seal functions as a return spring to retract the piston.

Question 13

Audible pad wear sensors have electrical contacts embedded in the linings. These contacts trigger the chime module when the pads wear down.

Question 14

Disc brakes require more force than drum brakes to achieve the same braking effort.

Question 15

A dust boot seal automatically adjusts caliper piston position.

Question 16

In most calipers, the dust boot is installed in the caliper bore groove before the piston is installed.

Question 17

Which of the following statements concerning the caliper assembly is NOT correct?

A) The caliper housing is usually a two-piece unit constructed from aluminum or cast iron
B) Caliper action converts hydraulic pressure to mechanical force
C) A caliper assembly can contain as many as four cylinder bores and pistons
D) The caliper assembly provides a means of forcing the brake pads against the rotor

Question 18

During pad replacement, some caliper pistons must be rotated with a special tool to retract all the way into the caliper bore.

Question 19

Most manufacturers recommend that the caliper mounting pins and their bushings be replaced each time the caliper is removed.

Question 20

Rear disc parking brakes have a mechanism that forces the pads against the rotor hydraulically.

Question 21

Which of the following statements concerning ceramic rotors is NOT true?

A) Ceramic rotors and the pads used with them wear out much faster than cast iron rotors
B) They weigh half as much as a conventional rotor, which reduces unsprung weight
C) They have excellent fade resistance and stopping power
D) The vehicle's wheels stay cleaner because no black brake dust is released

Question 22

Technician A says the caliper piston seal prevents leakage of brake fluid between the cylinder bore and the piston. Technician B says the caliper piston seal does not contribute to the piston's automatic adjustment feature. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 23

Technician A says that worn pad linings can cause rotor wear. Technician B says that hard spots in a rotor usually result from a manufacturing defect. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 24

Composite rotors are made of cast iron and ______.

A) steel
B) aluminum
C) carbon fiber
D) all answers are correct

Question 25

Technician A cleans brake components in denatured alcohol. Technician B cleans brake components in clean brake fluid. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 26

Large vehicles typically use ______ rotors.

A) solid
B) ventilated
C) two-piece
D) all answers are correct

Question 27

Technician A says some caliper designs use only one pad lining per brake assembly. Technician B says some disc brake pads have wear sensors. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 28

Technician A says a ventilated rotor helps cool the disc brake assembly. Technician B says the splash shield helps cool the disc brake assembly. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 29

Disc brake caliper pistons are being removed. Technician A positions a large dull screwdriver in the piston's dust boot groove to pry out the piston. Technician B injects 25 psi (172 kPa) of air pressure into the fluid line connection bore to remove the caliper piston. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 30

Linings are ____ to disc brake pads.

A) riveted
B) bonded
C) both "riveted" and "bonded"
D) neither "riveted" nor "bonded"

Question 31

What prevents moisture from entering the cylinder bore?

A) the phenolic piston
B) the caliper drag
C) the splash shield
D) the dust boot

Question 32

Technician A says a fixed rotor has an integral hub inside which the wheel bearings are mounted. Technician B says a floating rotor is less expensive than a fixed rotor and can be replaced easily and economically. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 33

Technician A replaces the pads if the linings are less than 1/8 inch (3.175 mm). Technician B says if the pad on one side of the caliper is worn more than the other side, the rotor has excess runout and must be replaced. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 34

The ball-and-ramp-type parking brake actuator is found on what make of vehicles?

A) GM
B) Ford
C) Toyota
D) Chrysler

Question 35

Caliper housings are made from ______.

A) aluminum
B) cast iron
C) both "aluminum" and "cast iron"
D) neither "aluminum" nor "cast iron"

Question 36

Rotors are typically made from ______.

A) aluminum
B) cast iron
C) both "aluminum" and "cast iron"
D) neither "aluminum" nor "cast iron"

Question 37

Technician A siphons out about two-thirds of the brake fluid from the master cylinder reservoir before beginning work on the pads or calipers. Technician B opens the caliper bleeder screws and runs a hose to a container to catch the fluid that is expelled,.while pushing the pistons back. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 38

Which of the following is NOT associated with a pedal pulsation problem?

A) air in the hydraulic system
B) excess lateral runout
C) excess parallelism
D) uneven wheel lug nut torque

Question 39

Technician A uses a minimum of 50 psi (345 kPa) of air pressure to force the piston from the caliper housing. Technician B heats the caliper housing with an oxyacetylene torch to boil the fluid and pop the piston out of the housing. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 40

Disc brake rotor conditions are being discussed. Technician A resurfaces the rotor if it has lateral runout, lacks parallelism, or is scored. Technician B resurfaces both the left and right rotors even if only one rotor has problems. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 41

Technician A says if the plated surface of a steel piston is worn, pitted, scored, or corroded, it can be lightly filed with a mill file then polished with emery cloth. Technician B says if there are any cracks, chips, or gouges in a phenolic piston, it must be replaced. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 42

The disc brake piston is made of steel, aluminum, or _____.

A) polycarbonate plastic
B) carbon fiber composite
C) phenolic resin
D) aramid fiber

Question 43

Technician A uses a C-clamp to push the piston back into its bore when replacing pads. Technician B supports the caliper using safety wire while servicing the brakes. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 44

Tapered roller bearings are being discussed. Technician A says the grease seal is installed on the outboard side of the bearing. Technician B says the outer cup, or race, is pressed into the hub. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 45

After new pads are installed, Technician A breaks in the new pads by making a half dozen or more hard stops from high speed to check whether the brakes will fade when hot. Technician B breaks in the new pads with several gentle to moderate stops, allowing time for the pads and rotors to cool between stops. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 46

A fixed caliper _____.

A) is bolted to the steering knuckle
B) has pistons on both sides of the rotor
C) does not move when the brakes are applied
D) all answers are correct

Question 47

Electronic pad wear warning systems are being discussed. Technician A says the pad wear sensors are wired in parallel. Technician B says the wear sensors are wired in series. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 48

The customer complains of a high-pitched squeal whenever the wheels are turning, except when the brakes are applied. Technician A says the pads are worn and need replacement. Technician B says the rotors are scored and must be replaced. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 49

A vibration or pulsation in the brake pedal when the brakes are applied is usually caused by ______.

A) warped rotors [runout]
B) oil or grease on the linings
C) frozen or sticking calipers
D) brake hose collapsed on the inside

Question 50

A hard pedal [abnormally high amount of pedal pressure is required to stop the vehicle] normally indicates a problem with the ______.

A) master cylinder
B) power brake booster
C) rotors
D) brake pads

Question 51

Technician A says unidirectional rotors can be installed on either the left side or right side of the car. Technician B says unidirectional rotors run cooler than conventional ventilated rotors. Who is correct?

A) A only
B) B only
C) both A and B
D) Neither a nor B

Question 52

The red Brake warning light is NOT turned on when ______.

A) the parking brake is set
B) the fluid level in the master cylinder is low
C) a fault in the ABS system is detected
D) there is a difference in pressure between brake circuits

Question 53

Caliper pistons that have threaded adjuster pushrods and internally threaded adjuster nuts are found on ______.

A) front wheel calipers
B) rear wheel calipers with auxiliary drum parking brakes
C) rear wheel actuating calipers
D) all answers are correct

Question 54

A brake inspection reveals that the outboard pad is significantly thinner than the inboard pad. Technician A says the problem could be a defective dust boot that caused the caliper to seize. Technician B says the problem could be caused by poor lubrication or deformation of the machined sliding areas on the caliper and/or anchor plate. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 55

Solid rotors are usually found on _____.

A) the front brakes of small, compact vehicles
B) the rear brakes of vehicles with rear disc brakes
C) the front brakes of large pickup trucks and SUVs
D) both "the front brakes of small, compact vehicles" and "the rear brakes of vehicles with rear disc brakes"

Question 56

Rear disc brakes with auxiliary drum parking brakes automatically adjust ______.

A) when the foot brake is applied in reverse
B) when the foot brake is applied in forward
C) when the parking brake is applied
D) none of these answers is correct

Question 57

What component in the brake caliper acts as a retracting mechanism for the piston when hydraulic pressure is released?

A) dust boot
B) square cut O-ring
C) caliper slide
D) accumulator piston

Question 58

Brake calipers are being discussed. Technician A says the bleeder screw is located at the bottom of the cylinder bore. Technician B says the fluid inlet hole is located at the top of the cylinder bore. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 59

Which of the following is NOT part of a caliper assembly?

A) piston
B) dust boot
C) anchor pin
D) square cut seal

Question 60

Technician A says floating calipers must be removed from the steering knuckle when replacing brake pads. Technician B says fixed calipers must be removed from the steering knuckle when replacing pads. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 61

Brake rotors should be checked for _____.

A) thickness
B) parallelism
C) runout
D) all answers are correct

Question 62

Improper tightening of the wheel lug nuts could cause the rotor to ____________________.

Question 63

A caliper piston is typically removed using a block of wood and ____________________

Question 64

A resurfaced rotor must be _____ inch thicker than the discard dimension to allow for wear.

A) .001 to .005
B) .005 to .010
C) .015 to .030
D) .040 to .080

Question 65

Technician A uses compressed air at 150 psi to remove the piston from the caliper bore. Technician B uses special internal expanding pliers to remove pistons from caliper bores. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 66

____________________ brakes cause poor fuel economy and generate destructive amounts of heat that can cause serious brake damage and brake failure.

Question 67

Front calipers are mounted to the____________________.

Question 68

Technician A readjusts the wheel bearings before measuring lateral runout. Technician B resurfaces or replaces rotors that have more than 0.003 inch of lateral runout. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 69

Technician A uses a dial indicator to measure parallelism. Technician B uses a dial indicator to measure runout. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 70

A vehicle has a frozen caliper on the left front wheel. The right front caliper is in good condition. Technician A installs a set of four new pads and a remanufactured caliper on the left side. Technician B installs loaded calipers on the left and right side. Who is correct?

A) A only
B) B only
C) both A and B
D) neither A nor B

Question 71

____________________ rotors are made of two different materials, usually cast iron and steel, to reduce weight.

Question 72

The inner and outer races of tapered roller bearings are ____________________ shaped.

Question 73

____________________ caliper disc brakes do not move when the brakes are applied.

Question 74

____________________ caliper disc brakes slide back and forth on pins or bolts.

Question 75

Some caliper assemblies can contain up to ____________________ cylinder bores and pistons.

Question 76

Air in the disc brake hydraulic system will cause a ____________________ pedal.

Question 77

____________________ bearings are the most common bearings used on the front wheels of RWD and the rear wheels of FWD vehicles.

Question 78

Unidirectional rotors have ____________________ cooling fins.

Question 79

On actuating calipers, the piston may have to be rotated before the _____ is (are) installed.

A) pads
B) dust boot
C) pin bushings
D) piston seal

Question 80

A ____________________ rotor has the hub and the rotor cast as a single unit.