Hummer H2. Manual — part 784

1. Raise and support the vehicle.

2. Remove the tire and wheel.

3. Remove the rear brake caliper bracket with the rear brake caliper. See BRAKE CALIPER BRACKET

under REMOVAL & INSTALLATION.

4. Remove the rear brake rotor. See BRAKE ROTOR under REMOVAL & INSTALLATION.

5. Inspect and replace the park brake shoe and lining if any excessive wear is indicated by the park brake

lining being worn down to the shoe, the brake lining is cracking or if there is oil or fluid contamination of
the brake lining.

6. Adjust the park brake shoe. See PARK BRAKE ADJUSTMENT .

7. Install the rear brake rotor. See BRAKE ROTOR under REMOVAL & INSTALLATION.

8. Install the rear brake caliper with the rear brake caliper bracket. See BRAKE CALIPER BRACKET

under REMOVAL & INSTALLATION.

9. Install the tire and wheel.

10. Lower the vehicle.

PARK BRAKE ADJUSTMENT

Park Brake Shoe Adjustment

1. Set the Drum-To-Brake Shoe Clearance Gage (J-21177-A) so that it contacts the inside diameter of the

rotor. See Fig. 10 .

2. Position the drum-to-brake shoe clearance gage over the shoe and the lining at the widest point. See Fig.

11 .

WARNING:

Avoid grinding brake linings, sanding brake linings or cleaning wheel
brake parts with a dry brush or with compressed air, when servicing
wheel brake parts. Some models or aftermarket brake parts may contain
asbestos fibers which can become airborne in dust. Breathing dust with
asbestos fibers may cause serious bodily harm. Use a water-dampened
cloth in order to remove any dust on brake parts. Equipment is available
commercially in order to perform this washing function. These wet
methods prevent fibers from becoming airborne.

WARNING:

Avoid grinding brake linings, sanding brake linings or cleaning wheel
brake parts with a dry brush or with compressed air, when servicing
wheel brake parts. Some models or aftermarket brake parts may contain
asbestos fibers which can become airborne in dust. Breathing dust with
asbestos fibers may cause serious bodily harm. Use a water-dampened
cloth in order to remove any dust on brake parts. Equipment is available
commercially in order to perform this washing function. These wet
methods prevent fibers from becoming airborne.

NOTE:

The park brake shoes must be adjusted before the park brake pedal is adjusted.

2004 Hummer H2

2003-04 BRAKES Disc - Hummer

3. Turn the adjuster nut until the lining just contacts the drum-to-brake shoe clearance gage.

4. Repeat steps 1 - 3 for the opposite side.

5. The clearance between the park brake shoe and the rotor is 0.026" (0.6604 mm).

Fig. 10: Setting Gauge On Inside Diameter Of Rotor
Courtesy of GENERAL MOTORS CORP.

2004 Hummer H2

2003-04 BRAKES Disc - Hummer

Fig. 11: Positioning Gauge On Shoe & Lining
Courtesy of GENERAL MOTORS CORP.

Park Brake Pedal Adjustment

Verify that the self adjuster lock-out pin has be removed. Fully apply and release the park brake pedal 3 times.

TROUBLESHOOTING

NOTE:

Before you adjust the park brake, verify that the park brake shoes are adjusted
to provide a clearance of 0.026" (0.6604 mm).

2004 Hummer H2

2003-04 BRAKES Disc - Hummer

DIAGNOSTIC STARTING POINTS

Hydraulic Brake System

Begin the system diagnosis by reviewing the system description and operation. See HYDRAULIC BRAKE
SYSTEM DESCRIPTION and HYDRAULIC BRAKE SYSTEM OPERATION under DESCRIPTION &
OPERATION. Reviewing the description and operation information will help you determine the correct
symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information
will also help you determine if the condition described by the customer is normal operation. See GENERAL
DIAGNOSIS in order to identify the correct procedure for diagnosing the system and where the procedure is
located.

Disc Brake System

Begin the disc brake system diagnosis with hydraulic brakes. See HYDRAULIC BRAKE SYSTEM . The use
of the diagnostic starting point will lead to the identification of the correct procedure for diagnosing the system
and where the procedure is located.

Park Brake System

Begin the system diagnosis by reviewing the system description and operation. See PARK BRAKE SYSTEM
DESCRIPTION and PARK BRAKE SYSTEM OPERATION under DESCRIPTION & OPERATION.
Reviewing the description and operation information will help you determine the correct symptom diagnostic
procedure when a malfunction exists. Reviewing the description and operation information will also help you
determine if the condition described by the customer is normal operation. See PARK BRAKE SYSTEM under
GENERAL DIAGNOSIS in order to identify the correct procedure for diagnosing the system and where the
procedure is located.

GENERAL DIAGNOSIS

Hydraulic Brake System

Perform the brake system vehicle road test before using the brake symptom tables in order to duplicate the
customer's concern. See BRAKE SYSTEM VEHICLE ROAD TEST . Review the system description and
operation in order to familiarize yourself with the system functions. See DESCRIPTION & OPERATION .

Inspect for aftermarket devices which could affect the operation of the hydraulic brake system. See
CHECKING AFTERMARKET ACCESSORIES . Inspect the easily accessible or visible system
components for obvious damage or conditions which could cause the symptom. Inspect the brake fluid reservoir
for the proper brake fluid level. Faulty electrical connections or wiring may be the cause of intermittent
conditions.

Park Brake System

Review the system operation in order to familiarize yourself with the system functions. See PARK BRAKE
SYSTEM under DESCRIPTION & OPERATION.

2004 Hummer H2

2003-04 BRAKES Disc - Hummer