Text preview for : en_4j2_4e1.pdf part of Daewoo Nubira/Lacetti Also known as: Chevrolet Nubira / Lacetti, Chevrolet Optra Optra5, Suzuki Forenza Reno Covers the 1.4L, 1.6L and 1.8L engine. Year 2004



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SECTION : 4E1

REAR DISC BRAKES
TABLE OF CONTENTS
SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­1 Fastener Tightening Specifications . . . . . . . . . . 4E1­1 DIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­1 Lining Inspection . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­1 Rotor Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­1 MAINTENANCE AND REPAIR . . . . . . . . . . . . . . 4E1­3 ON­VEHICLE SERVICE . . . . . . . . . . . . . . . . . . . . 4E1­3 Shoe and Lining . . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­3 Caliper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­4 Rotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­5 Hub and Parking Brake Shoe/Backplate . . . . . 4E1­6 UNIT REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­10 Caliper Overhaul . . . . . . . . . . . . . . . . . . . . . . . . 4E1­10 GENERAL DESCRIPTION AND SYSTEM OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4E1­12 Disc Brake Caliper Assembly . . . . . . . . . . . . . . 4E1­12

SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
Application Brake Hose Inlet Bolt and Ring Seals Caliper Mounting Bolts Lower Caliper Mounting Bolt Parking Brake Shoe Hold­Down Spring Assembly Screw Rotor Detent Screw Hub Bolts NSm 32 56 27 4 4 65 Lb­Ft 24 41 20 ­ ­ 48 Lb­In ­ ­ ­ 35 35 ­

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

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

Important : The minimum discard thickness of the brake shoe lining is 2 mm (0.08 inch). 5. 6. 7. Install the shoes in axle sets only. Install the rear wheels. Refer to Section 2E, Tires and Wheels. Lower the vehicle.

4E1 ­ 2IREAR DISC BRAKES
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. 2. To preserve wheel balance, mark the relative positions of the wheel and hub, and remove the rear wheel. Fasten the brake rotor to the wheel hub. Mount a dial indicator on the brake caliper. 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. After measuring is completed, remove the dial indicator and the wheel nuts. If necessary, refinish the rotor with precision equipment. Measure the runout again after refinishing. If the runout exceeds 0.8 mm (0.03 inch) after refinishing, the rotor should be replaced. Align the marks that were made before wheel removal, and install the rear wheel. Lower the vehicle.

3. 4. 5.

6. 7.

8. 9. 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 0.8 mm (0.03 inch). If lateral runout exceeds the specification, make sure that there is no dirt between the rotor and the hub and that hub­to­rotor 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.

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REAR DISC BRAKES 4E1 ­ 3

MAINTENANCE AND REPAIR
ON­VEHICLE SERVICE SHOE AND LINING
Removal Procedure
1. 2. Raise and suitably support the vehicle. Remove the rear wheels. Refer to Section 2E, Tires and Wheels. 3. Remove the lower caliper guide pin bolt. Important : Caliper removal is not necessary to service the brake pads.

4. 5.

Pivot the caliper upward. Remove the brake shoes.

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

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4E1 ­ 4IREAR DISC BRAKES
Notice : Avoid damaging the piston seal when the piston housing is pulled down. 4. Pivot the caliper downward and install the bolt.

Tighten
5. 6. Tighten the lower caliper mounting bolt to 27 NSm (20 lb­ft). Install the rear wheels. Refer to Section 2E, Tires and Wheels. Lower the vehicle.

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

3.

4.

5. 6.

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

Installation Procedure
1. Install the caliper with the mounting bolts.

Tighten
Tighten the caliper mounting bolts to 56 NSm (41 lb­ ft).

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REAR DISC BRAKES 4E1 ­ 5
2. Connect the brake hose with the bolt and ring seals.

Tighten
3. 4. 5. 6. Tighten the brake hose inlet bolt and ring seals to 32 NSm (24 lb­ft). Install the rear wheels. Refer to Section 2E, Tires and Wheels. Lower the vehicle. Fill the master cylinder to the proper level with clean brake fluid. Bleed the caliper. Refer to Section 4F, Antilock Brake System and Traction Control System.

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

4. 5.

Remove the rotor detent screw. Remove the rotor.

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.

Tighten
Tighten the rotor detent screw to 4 NSm (35 lb­in)

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4E1 ­ 6IREAR DISC BRAKES
2. Apply a few drops of thread­locking compound to the caliper bracket mounting bolts and install the caliper bracket.

Tighten
3. Tighten the caliper bracket mounting bolts to 56 NSm (41 lb­ft). Install the brake shoes and the caliper. See "Caliper" in this section.

HUB AND PARKING BRAKE SHOE/BACKPLATE
Removal Procedure
1. Remove the caliper mounting bracket.

2. 3.

Remove the rotor detent screw. Remove the rotor.

4.

Remove the rear ABS sensor connector.

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REAR DISC BRAKES 4E1 ­ 7
5. Remove the hub bolts and hub.

6.

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

7. 8.

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

9.

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

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4E1 ­ 8IREAR DISC BRAKES Installation Procedure
1. Install the parking brake cable to the backing plate and lock the pin.

2.

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

3.

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

4.

Install the hub with bolts.

Tighten
Tighten the hub bolts to 65 NSm (48 lb­ft).

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REAR DISC BRAKES 4E1 ­ 9
5. Connect the ABS sensor connector.

6.

Install the rotor with detent screw.

Tighten
Tighten the rotor detent screw to 4 NSm (35 lb­in).

7.

Install the caliper mounting bracket with bolts.

Tighten
8. Tighten the caliper bracket mounting bolts to 56 NSm (41 lb­ft). Install the wheel.

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4E1 ­ 10IREAR DISC BRAKES

UNIT REPAIR CALIPER OVERHAUL
Remove the caliper. Refer to "Caliper" in this section. 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 rolled­up shop towels beneath the caliper to prevent damage to the piston. 2. Apply unlubricated compressed air at the hose inlet of the caliper. 3. 4. Remove the piston from its bore and remove the piston dust seal. Remove the inner seal from the bore. Avoid scratching the bore. 1.

5.

Remove the bleeder valve dust cap and the bleeder valve.

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. Inspect the piston and caliper for scoring, nicks, or corrosion. Replace any components which show these conditions.
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2.

REAR DISC BRAKES 4E1 ­ 11
3. Install the bleeder valve and the dust cap.

3. 4.

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

5. 6. 7.

8. 9.

Install the piston dust seal in its groove. Lubricate the piston with brake fluid. 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. Reinstall the caliper. Refer to "Caliper" in this section. Bleed the brake system. Refer to Section 4F, Anti­ lock Brake System.

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4E1 ­ 12IREAR DISC BRAKES

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.

S S S S

S S S

Replace all components included in the repair kits used to service the caliper. Lubricate the rubber parts with clean brake fluid to ease assembly. Do not use lubricated shop air on brake parts, as damage to the rubber components may result. If any hydraulic component is removed or disconnected, it may be necessary to bleed all or part of the brake system. Refer to Section 4F, Anti­lock Brake System. Replace the shoes in axle sets only. The torque values specified are for dry, unlubricated fasteners. Perform the service operations on a clean bench, free from oily material.

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