Page 721 of 2100
5C±41 POWER±ASSISTED BRAKE SYSTEM
5. Apply special grease (approximately 1 g) to the piston
and attach the dust boot to the piston and caliper.
Insert the dust boot ring into the dust boot.
302RS020
6. Install guide bolt and lock bolt dust boot.
7. Install the dust boot on the support bracket after
applying special grease (approximately 1 g) onto the
dust boot inner surface. Apply special grease onto the
lock bolt and guide bolt setting hole of the support
bracket.
302RS021
8. Install lock bolt and guide bolt and tighten the bolt to
the specified torque.
Torque: 74 N´m (54 lb ft)
Page 730 of 2100
5C±50
POWER±ASSISTED BRAKE SYSTEM
302RW017
7. Install the wheel and tire assembly, refer to Wheels
and Tires System
in Section 3E.
8. Bleed brakes. Refer to
Hydraulic Brakes in this
section.
Rear Disc Brake Caliper (4y4 Model)
Rear Disc Brake Caliper Disassembled View
306RW014
Legend
(1) Guide Bolt
(2) Lock Bolt
(3) Bleeder with Cap
(4) Caliper Body(5) Piston Seal
(6) Piston
(7) Dust Boot: Piston
(8) Dust Boot Ring
(9) Dust Boot: Guide Bolt and Lock Bolt
Page 731 of 2100

5C±51 POWER±ASSISTED BRAKE SYSTEM
Disassembly
1. Remove guide bolt.
2. Remove lock bolt.
3. Remove dust boot; guide bolt and lock bolt.
4. Remove dust boot ring, using a small screwdriver.
302RS016
5. Insert a block of wood into the caliper and force out
the piston by blowing compressed air into the caliper
at the flexible hose attachment. This procedure must
be done prior to removal of the dust boot.
Remove piston.
WARNING: D O N O T P L A C E Y O U R F I N G E R S I N
FRONT OF THE PISTON IN AN ATTEMPT TO CATCH
OR PROTECT IT WHEN APPLYING COMPRESSED
AIR. THIS COULD RESULT IN PERSONAL INJURY.
CAUTION: Use just enough air to ease the piston
out of the bore. If the piston is blown out, it may be
damaged.
302RS017
6. Remove dust boot: piston.
7. Remove piston seal.
8. Remove bleeder with cap.
9. Remove caliper body.
Inspection and Repair
Make necessary parts replacement, if wear, damage,
corrosion or any other abnormal conditions are found
through inspection.
Check the following parts:
Rotor
Cylinder body
Cylinder bore
Piston
Guide bolt, lock bolt
Support bracket
NOTE: The piston dust seal and dust boot are to be
replaced each time the caliper is overhauled. Discard
these used rubber parts and replace with new ones.
Reassembly
1. Install caliper body.
2. Install bleeder with cap and tighten the cap to the
specified torque.
Torque: 8 N´m (69 lb ft)
3. Install piston seal and apply special rubber grease to
the piston seal and cylinder wall, then insert the piston
seal into the cylinder. The special rubber grease is
included in the repair kit.
302RS018
4. When inserting the piston into the cylinder, use finger
pressure only and do not use a mallet or other impact
tool, since damage to the cylinder wall or piston seal
can result.
Install piston.
Page 732 of 2100
5C±52
POWER±ASSISTED BRAKE SYSTEM
302RS019
5. Apply special grease (approximately 1g) to the piston
and attach the dust boot to the piston and caliper.
Insert the dust boot ring into the dust boot.
302RS020
6. Install guide bolt and lock bolt dust boot.
7. Install the dust boot on the support bracket after
applying special grease (Approx. 1g) onto the dust
boot inner surface. Also apply special grease onto
the lock bolt and guide bolt setting hole of the support
bracket.
302RS021
8. Install lock bolt and guide bolt and tighten the bolt to
the specified torque.
Torque: 44 N´m (32 lb ft)
Page 738 of 2100
5C±58
POWER±ASSISTED BRAKE SYSTEM
Disassembled View
305RS006
Legend
(1) Boot
(2) Piston Assembly
(3) Piston Cup
(4) Return Spring
(5) Bleeder
(6) Wheel Cylinder
Disassembly
1. Remove boot (1) and piston assembly (2).
2. Remove piston cup (3) from piston assembly (2).
3. Remove return spring (4) and bleeder (5) from wheel
cylinder (6).
Inspection and Repair
1. Make necessary parts replacement if wear, damage,
corrosion or any other abnormal condition are found
through inspection.
Check the following parts;
Wheel cylinder body
Cylinder bore
Piston
Return spring
BleederNOTE: Replace the piston cups and boots each time the
wheel cylinder is overhauled. Discard these used rubber
parts and replace with new ones.
Reassembly
1. Lubricate the cylinder bore with clean rubber grease.
305RS007
2. Install bleeder (5) to wheel cylinder (6).
Torque: 10 N´m (8 lb ft)
305RS008
Page 739 of 2100
5C±59 POWER±ASSISTED BRAKE SYSTEM
3. Install new piston cups (3) on each piston so that the
flared end of the cups are turned to the inboard side of
the pistons.
Attach the return spring (4) and the boot (1) to the
piston.
305RS009
4. Apply DELCO silicone lube No. 5459912 (or
equivalent) to the piston and the inner face of the
boots.
5. Install piston assembly (2) to wheel cylinder (6).
Page 778 of 2100
5C±98
POWER±ASSISTED BRAKE SYSTEM
Front Disc Brake Caliper
Front Disc Brake Caliper Disassembled View
302R200018
Legend
(1) Bleeder with Cap
(2) Caliper Body(3) Piston
(4) Piston Seal
(5) Dust Boot: Piston
Disassembly
1. Insert a block of wood into the caliper and force out
the piston by blowing compressed air into the caliper
at the flexible hose attachment. This procedure must
be done prior to removal of the dust boot.
Remove piston.
WARNING: D O N O T P L A C E Y O U R F I N G E R S I N
FRONT OF THE PISTON IN AN ATTEMPT TO CATCH
OR PROTECT IT WHEN APPLYING COMPRESSED
AIR. THIS COULD RESULT IN PERSONAL INJURY.
CAUTION: Use just enough air to ease the piston
out of the bore. If the piston is blown out, it may be
damaged.
302R200012
Page 779 of 2100

5C±99 POWER±ASSISTED BRAKE SYSTEM
2. Remove dust boot: piston.
3. Remove piston seal.
4. Remove bleeder with cap.
5. Remove caliper body.
Inspection and Repair
Make necessary parts replacement, if wear, damage,
corrosion or any other abnormal conditions are found
through inspection.
Check the following parts:
Rotor
Cylinder body
Cylinder bore
Piston
Guide pin, lock pin
Support bracket
NOTE: The piston seal, boot ring and dust boot are to be
replaced each time the caliper is overhauled. Discard
these used rubber parts and replace them with new ones.
Reassembly
1. Install caliper body.
2. Install bleeder with cap and tighten the cap to the
specified torque.
Torque: 8 N´m (69 lb in)
3. Apply special rubber grease to the piston seal and
cylinder wall, then insert the piston seal into the
cylinder. The special rubber grease is included in the
repair kit.
302R200013
4. When inserting the piston into the cylinder, use finger
pressure only and do not use a mallet or other impact
tool, since damage to the cylinder wall or piston seal
can result.
Install piston.
302R200015
5. Apply special grease (approximately 1 g) to the piston
and attach the dust boot to the piston and caliper.
Insert the dust boot ring into the dust boot.
6. Install guide bolt and lock bolt dust boot.
7. Install the dust boot on the support bracket after
applying special grease (approximately 1 g) onto the
dust boot inner surface. Apply special grease onto the
lock pin and guide pin setting hole of the support
bracket.
302R200022
Legend
(1) Guide Pin
(2) Lock Pin
(3) Pin Boot
8. Install pin bolt and tighten the bolt to the specified
torque.
Torque: 45 N´m (33 lb ft)