GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

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

1

Were you sent here from the Hydraulic Brake Symptom table?

Go to Step 2

Go to Symptoms - Hydraulic Brakes

2

  1. Inspect the disc brake system for the following conditions.
  2. • 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
  3. Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis.

Did you find and correct a condition?

Go to Step 6

Go to Step 3

3

  1. Inspect the brake assist system for the following conditions.
  2. • 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
  3. Adjust, repair or replace components as necessary.

Did you find and correct a condition?

Go to Step 6

Go to Step 4

4

  1. Inspect the hydraulic brake system for the following conditions.
  2. • Improper operation of caliper pistons
    • Contaminated brake fluid
  3. Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis.

Did you find and correct a condition?

Go to Step 6

Go to Step 5

5

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

Did you find and correct a condition?

Go to Step 6

Go to Symptoms - Hydraulic Brakes

6

  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