Hummer H3. Manual — part 1309

BRAKE SYSTEM NOISE

Brake System Noise

2

Excessive corrosion of rotor
friction surfaces; including red,
gray or black oxidation

Loose, damaged or missing
caliper or lining hardware

Bent or damaged caliper or
mounting component

Excessive LRO of wheel
hub/axle flange; due to damage
and/or loose or excessively worn
bearings

2. Adjust, repair or replace components

as necessary. Refer to Disc Brake
System Diagnosis.

Did you find and correct a condition?

Go to Step 3

Go to
Diagnostic
Starting Point -
Hydraulic
Brakes

3

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

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
Diagnostic
Starting Point -
Hydraulic
Brakes

1. Inspect the disc brake system for the

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

2

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 9

Go to Step 3

1. Inspect the brake assist system for the

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

3

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 9

Go to Step 4

1. Inspect the hydraulic brake system

for the following conditions.

Improper operation of caliper
pistons

Contaminated brake fluid

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

4

2. Adjust, repair or replace components

as necessary. Refer to Hydraulic
Brake System Diagnosis.

Did you find and correct a condition?

Go to Step 9

Go to Step 5

5

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

Go to Step 6

Go to Step 9

6

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 7

Go to Step 9

7

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 9

Go to Step 8

8

Inspect the park brake system for proper
operation. Refer to Park Brake System
Diagnosis .
Did you find and correct a condition?

Go to Step 9

Go to
Diagnostic
Starting Point -
Hydraulic
Brakes

9

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

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3