Parking Brake Adjustment - GMC G Service Manual

4. Return spring guide (72).
5. Hold-down clips (65).
6. Hold-down springs (64).
7. Washers (63).
8. Lever strut (55).
9. Strut spring (57).
10. Lever retaining ring (67).
11. Shoes (68).
12. Adjusting screw (60).
\ 1 *\
13. Adjusting screw spring (58).
Inspect
• All parts for discoloration due to heat or stress.
Replace if necessary.
• Brake drum for scoring and heat spots. Machine drum
if needed.
F I Install or Connect (Figure 26)
• Lubricate the shoe pads and adjusting screw threads
with a thin coat of white lithium grease.
1. Adjusting screw (60) and adjusting screw spring (58)
to both shoes (68).
2. Shoe assembly (68).
3. Lever retaining ring (67).
4. Lever strut (55) and strut spring (57).
5. Washers (63).
6. Hold-down springs (64).
7. Hold-down clips (65).
8. Return spring guide (72).
9. Return springs (56 and 71).
10. Drum (66).
11. Propeller shaft. Refer to PROPELLER SHAFT
(SEC. 4A).
| / | Adjust
• Parking brake. Refer to "Parking Brake Adjust­
ment" in this section.
• Lower the vehicle.

PARKING BRAKE ADJUSTMENT

The parking brakes must be adjusted whenever the
parking brake cables have been replaced or disconnected,
or if the brake holding ability is not adequate. Before adjust­
ing the parking brakes, check the condition of the service
brakes. The service brakes must be adjusted properly
before proceeding with the parking brake adjustment.
CABLE INSPECTION
Check the parking brake system for free operation. The
brake lever must return to the released position without
sticking or binding. If a problem is present, check the cable
routings for kinks or binding. Clean and lubricate the park­
ing brake assembly and cables with Delco Brake Lube or
equivalent.
HYDRAULIC BRAKES 5A-25
FOOT PEDAL TYPE
• Block the front wheels.
• Raise and support the rear axle with suitable safety
stands.
1. Loosen the equalizer nut.
2. Set the parking brake pedal to four clicks.
| ? l Adjust
Equalizer nut until the wheels rotate forward with a
moderate drag.
3. Release the parking brake and rotate the rear wheels.
There should be no brake drag.
• Lower the vehicle.
• Unblock the front wheels.
LEVER TYPE
• Block the front wheels.
• Raise and support the rear axle with suitable safety
stands.
1. Turn the adjusting knob on the parking brake lever
counterclockwise until it stops.
• Apply parking brake.
2. Loosen the equalizer nut.
Adjust
Equalizer nut until a light drag is felt while rotating the
wheels forward.
Knob on the parking brake lever until a definite snap
over center is felt.
3. Release the parking brake and rotate the rear wheels.
There should be no brake drag.
• Lower the vehicle.
• Unblock the front wheels.
INTERNAL EXPANDING (PROPELLER SHAFT)
CAUTION: See "Caution" on page 5A-1 of this
section.
• Block the front wheels.
• Raise and support the rear axle with suitable safety
stands.
1. Remove the clevis pin connecting the pull rod and
relay lever.
2. Rotate the brake drum to align the access hole with
the adjusting screw.
• Manual transmissions — the adjusting screw
is located at the bottom of the shoe.
• Automatic transmission — the adjusting
screw is located at the top of the shoe.
• When adjusting the parking brake for the first
time, it will be necessary to remove the lanced
area from the drum. The drum must be removed
to clean out all the metal shavings. Refer to
PROPELLER SHAFT (SEC. 4A).
26