DEFINITION: Vehicle exhibits abnormal noise when braking; vehicle may exhibit abnormal noise during motion just after brake pedal release.

Were you sent here from the Hydraulic Brake Symptom table?

Go to Step 2

Go to Diagnostic Starting Point - Hydraulic Brakes

1. Inspect the disc brake system for the following conditions.

•	Lining wear indicator contact with rotor

•	Debris trapped between rotor and splash shield or backing plate; and/or debris trapped between rotor and linings

•	Contaminated linings

•	Aftermarket linings

•	Glazed linings

•	Distorted, cracked or damaged linings

•	Excessively worn linings

•	Damaged or excessively worn caliper hardware and/or lining hardware

•	Incorrectly installed, loose or missing caliper hardware and/or lining hardware

•	Lack of lubrication or excessive corrosion on metal to metal contact surfaces

•	Bent or damaged splash shield or backing plate

•	Hard spots, heat checks, blueing discoloration of rotor friction surfaces

•	Glazed rotor friction surfaces

•	Bent or damaged caliper or mounting component

2. Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis.

Did you find and correct a condition?

Go to Step 10

Go to Step 3

1. Inspect the drum brake system, if equipped, for the following conditions.

•	Glazed linings

•	Contaminated linings

•	Aftermarket linings

•	Distorted, damaged or excessively worn linings

•	Improper adjustment

•	Weak or damaged return spring or springs

•	Weak or damaged hold down spring or springs

•	Cracked, scored, excessively worn or damaged drum

•	Out of round or damaged drum

•	Hard spots, heat checks, blueing discoloration of drum friction surface

•	Threaded or spiral grooves in drum friction surface

•	Distorted or damaged backing plate

•	Lack of lubrication on backing plate

•	Excessive dust or foreign matter in drum

2. Adjust, repair or replace components as necessary. Refer to Drum Brake System Diagnosis.

Did you find and correct a condition?

Go to Step 10

Go to Step 4

1. Inspect the brake assist system for the following conditions.

•	Lack of lubrication or excessively worn pushrod or pedal pivots or pivot bushings

•	Bent or damaged pedal pushrod, pedal, or pedal bracket

•	Damaged or improperly operating vacuum booster and/or check valve, if equipped

•	Low power steering fluid level, if equipped with hydraulic boost

•	Improperly tensioned, excessively worn or damaged power steering belt, if equipped with hydraulic boost

•	Restricted return hose from hydraulic booster, if equipped

•	Improperly operating hydraulic booster, if equipped

•	Improperly functioning power steering system, if equipped with a hydraulic booster assembly

•	Contaminated power steering fluid, if equipped with hydraulic boost

2. Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis.

Did you find and correct a condition?

Go to Step 10

Go to Step 5

1. Inspect the hydraulic brake system for the following conditions.

•	Improper operation of wheel cylinder pistons, if equipped

•	Improper operation of caliper pistons

•	Contaminated brake fluid

2. Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis.

Did you find and correct a condition?

Go to Step 10

Go to Step 6

Is the vehicle equipped with a drum-in-rotor type of park brake system?

Go to Step 7

Go to Step 9

Ensure the park brake shoes are not adjusted too tightly, possibly causing a noise under certain conditions.

Are the park brake shoes adjusted too tightly?

Go to Step 8

Go to Step 9

1. Clean and inspect the park brake shoes for excessive wear and/or damage.
2. Inspect the drum portion of the rotors for excessive wear, blueing discoloration, heat spots, and excessive radial runout.
3. If any of these conditions are present, replace the affected components.
4. Adjust the park brake system.

Did you find and correct a condition?

Go to Step 10

Go to Step 9

Inspect the park brake system for proper operation. Refer to Park Brake System Diagnosis .

Did you find and correct a condition?

Go to Step 10

Go to Diagnostic Starting Point - Hydraulic Brakes

1. Install or connect components that were removed or disconnected during diagnosis.
2. Road test the vehicle in order to confirm proper operation. Refer to Brake System Vehicle Road Test .

Is the condition still present?

Go to Step 2

System OK