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SECTION 4E1

REAR DISC BRAKES

SPECIFICATIONS

General Specifcations

.
1.4/1.6/1.8/2.0 DOHC Engine
Application
Millimeters
Inches
Rear Brake Rotors:
.
.
Discard Thickness
Lateral Runout (Installed)
Rotor Diameter
Rotor Thickness (New)
Thickness Variation
8
0.08
258
10.4
0.01
0.31
0.003
10.15
0.40
0.0004
Caliper:
.
.
Minimum Piston Diameter (Rear)
32
1.260

Fastener Tightening Specifications

Application
N•m
Lb-Ft
Lb-In
Brake Hose Inlet Bolt and Ring Seals
32
24
-
Caliper Mounting Bolts
56
41
-
Lower Caliper Mounting Bolt
27
20
-
Parking Brake Shoe Hold-Down Spring Assembly Screw
4
-
35
Rotor Detent Screw
4
-
35
Hub Bolts
65
48
-

DIAGNOSIS

Lining Inspection

  1. Raise and suitably support the vehicle.
  2. Remove the rear wheels. Refer to Section 2E, Tires and Wheels.
  3. Visually check the brake shoe linings for minimum thickness and wear.
  4. Measure the thickness.

Important : The minimum discard thickness of the brake shoe lining is 2 mm (0.08 inch).

  1. Install the shoes in axle sets only.
  2. Install the shoes in axle sets only.
  3. Install the rear wheels. Refer to Section 2E, Tires and Wheels.
  4. Lower the vehicle.

Rotor Inspection

Brake rotors are manufactured with close tolerances for thickness variation, flatness, and lateral runout, but pits and grooves are created in rotors during usage. Lack of uniformity of the braking surfaces of the rotor can cause inadequate braking and a pulsating pedal during braking. The surface finish of the rotor is also important because an unsuitable surface finish can cause pulling and rapid wear of the brake shoe lining. If a rotor does not meet the specification, it should be refinished to specification or replaced. Refinishing of the rotor should only be done with precision equipment.
Thickness variation can be checked by measuring the thickness of the rotor at four or more points around the circumference of the rotor. All measurements must be made at the same distance from the edge of the rotor. A rotor that varies by more than. 1.0 mm (0.04 inch) can cause pedal pulsation and/or front end vibration during braking. Thickness can be measured with a commercially available micrometer and should be 10 mm(0.39 inch) or over.

V3B34E02
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Light scoring of the rotor surfaces is acceptable if it does not exceed 0.40 mm (0.016 inch) in depth. Scoring measurements can be made with a commercially available brake micrometer.
Lateral runout cannot exceed 0.08 mm (0.003 inch). If lateral runout exceeds the specification, make sure that there is no dirt between the rotor and the hub and that hub-to-rotor contact surfaces are smooth and free from burrs. Use a commercially available dial indicator to check the lateral runout according to the following procedure.
  1. Position the shift lever in NEUTRAL and raise the vehicle.
  2. To preserve wheel balance, mark the relative positions of the wheel and hub, and remove the rear wheel.
  3. Fasten the brake rotor to the wheel hub.
  4. Mount a dial indicator on the brake caliper.
  5. Place the indicator tip approximately 10 mm (0.39 inch) from the outer edge of the brake rotor, perpendicular to the disc and under slight preload. Observe the indicator gauge while rotating the rotor.
  6. After measuring is completed, remove the dial indicator and the wheel nuts.
  7. If necessary, refinish the rotor with precision equipment. Measure the runout again after refinishing. If the runout exceeds 0.08 mm (0.003 inch) after refinishing, the rotor should be replaced.
  8. Align the marks that were made before wheel removal, and install the rear wheel.
  9. Lower the vehicle.

V3B34E03
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MAINTENANCE AND REPAIR

ON-VEHICLE SERVICE


J3B14E01
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Shoe and Lining

Removal Procedure

  1. Raise and suitably support the vehicle.
  2. Remove the rear wheels. Refer to Section 2E, Tires and Wheels.
  3. Remove the lower caliper guide pin bolt.

    4. Important : Caliper removal is not necessary to service the brake pads.


    J3B14E02
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  4. Pivot the caliper upward.
  5. Remove the brake shoes.

J3B14E02
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Installation Procedure

  1. Measure the minimum brake shoe lining thickness. Refer to "Lining Inspection" in this section.
  2. Install the brake shoes into the caliper.
  3. Push the piston inward, if needed.

    4. J3B14E01
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    Notice : Avoid damaging the piston seal when the piston housing is pulled down.

  4. Pivot the caliper downward and install the bolt.

    5. Tighten
    Tighten the lower caliper mounting bolt to 27 N•m (20 lb-ft).

  5. Install the rear wheels. Refer to Section 2E, Tires and Wheels.
  6. Lower the vehicle.

J3B14E03
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Caliper

Removal Procedure

  1. Raise and suitably support the vehicle.
  2. Mark the position of the rear wheels relative to the wheel hubs and remove the wheels. Refer to Section 2E, Tires and Wheels.
  3. Remove the bolt and the ring seals that attach the brake hose inlet fitting to the caliper.

    4. J3B14E04
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  4. Disconnect the brake hose. Plug the openings in the caliper and the brake hose to prevent fluid loss or contamination.
  5. Remove the caliper mounting bolts from the steering knuckle.
  6. Remove the caliper.

J3B14E04
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Installation Procedure

  1. Install the caliper with the mounting bolts.

    2. Tighten
    Tighten the caliper mounting bolts to 56 N•m (41 lb-ft).


    J3B14E03
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  2. Connect the brake hose with the bolt and ring seals.

    3. Tighten
    Tighten the brake hose inlet bolt and ring seals to 32 N•m (24 lb-ft).

  3. Install the rear wheels. Refer to Section 2E, Tires and Wheels.
  4. Lower the vehicle.
  5. Fill the master cylinder to the proper level with clean brake fluid.
  6. Bleed the caliper. Refer to Section 4F, Antilock Brake System.

J3B14E04
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Rotor

Removal Procedure

  1. Remove the caliper. Refer to "Caliper" in this section.
  2. Remove the brake shoes.
  3. Remove the caliper mounting bracket.

    4. J3B14E05
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  4. Remove the rotor detent screw.
  5. Remove the rotor.

J3B14E05
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Installation Procedure

    Important : To guarantee uniform braking, always refinish both rotors even if only one rotor is defective.

  1. Install the rotor on the front wheel hub and install the detent screw.

    2. Tighten
    Tighten the rotor detent screw to 4 N•m (35 lb-in)


    J3B14E04
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  2. Apply a few drops of thread-locking compound to the caliper bracket mounting bolts and install the caliper bracket.

    3. Tighten
    Tighten the caliper bracket mounting bolts to 56 N•m (41 lb-ft).

  3. Install the brake shoes and the caliper. See "Caliper" in this section.

J3B14E04
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Hub and Parking Brake Shoe/Backplate

Removal Procedure

  1. Remove the caliper mounting bracket.

    2. J3B14E05
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  2. Remove the rotor detent screw.
  3. Remove the rotor.

    4. J3B14E06
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  4. Remove the rear ABS sensor connector.

    5. J3B14E07
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  5. Remove the hub bolts and hub.

    6. J3B14E08
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  6. Remove the upper return spring, lower return spring and adjuster assembly.

    7. J3B14E09
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  7. Remove the retaining spring plate, spring and retaining spring pin.
  8. Remove the parking brake shoe.

    9. J3B14E10
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  9. Remove the parking brake cable pin and cable from the backing plate.

J3B14E10
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Installation Procedure

  1. Install the parking brake cable to the backing plate and lock the pin.

    2. J3B14E09
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  2. Install the retaining spring pin, parking brake shoe, retaining spring and retaining spring plate.

    3. J3B14E08
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  3. Install the adjuster assembly, lower return spring and upper return spring.

    4. J3B14E07
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  4. Install the hub with bolts.

    5. Tighten
    Tighten the hub bolts to 65 N•m (48 lb-ft).


    J3B14E06
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  5. Connect the ABS sensor connector.

    6. J3B14E05
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  6. Install the rotor with detent screw.

    7. Tighten
    Tighten the rotor detent screw to 4 N•m (35 lb-in).


    J3B14E04
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  7. Install the caliper mounting bracket with bolts.

    8. Tighten
    Tighten the caliper bracket mounting bolts to 56 N•m (41 lb-ft).

  8. Install the wheel.

UNIT REPAIR


C407E002
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Caliper Overhaul

  1. Remove the caliper. Refer to "Caliper" in this section.

    2. Caution : Do not attempt to catch the piston when attempting to remove the piston with compressed air. The piston will pop out of its bore with enough force to damage a hand or fingers.

    Important : When removing the caliper piston with compressed air, place some rolled-up shop towels beneath the caliper to prevent damage to the piston.

  2. Apply unlubricated compressed air at the hose inlet of the caliper.

    3. C407E003
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  3. Remove the piston from its bore and remove the piston dust seal.
  4. Remove the inner seal from the bore. Avoid scratching the bore.

    5. C107E125
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  5. Remove the bleeder valve dust cap and the bleeder valve.

C107E125
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Assembly Procedure

    Important : Do not use a hone or any other procedure to remove material from the caliper bore or the piston.

  1. Clean all parts in denatured alcohol or brake fluid. Dry the parts with unlubricated compressed air and blow out all passages in the housing and the bleeder valve.
  2. Inspect the piston and caliper for scoring, nicks, or corrosion. Replace any components which show these conditions.

  3. Install the bleeder valve and the dust cap.

    4. C107E127
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  4. Lubricate a new piston inner seal with brake fluid.
  5. Install the piston inner seal into the groove in the caliper bore.

    6. C407E004
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  6. Install the piston dust seal in its groove.
  7. Lubricate the piston with brake fluid.
  8. Push the piston inward until it is properly seated. Make sure that the dust seal is in the correct groove in the piston and the caliper.
  9. Reinstall the caliper. Refer to "Caliper" in this section.
  10. Bleed the brake system. Refer to Section 4F, Antilock Brake System.

GENERAL DESCRIPTION AND SYSTEM OPERATION

Disc Brake Caliper Assembly

The caliper has a single bore and is mounted to the steering knuckle with two mounting bolts. Hydraulic pressure, created by applying the brake pedal, is converted by the caliper to a stopping force. This force acts equally against the piston and the bottom of the caliper bore to move the piston outward and to slide the caliper inward, resulting in a clamping action on the rotor. This clamping action forces the linings against the rotor, creating friction to stop the vehicle.
Important :



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