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Disc Brake System Testing

WARNING: This page is about a different car, the 2002 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
  1. Were you sent here from TROUBLESHOOTING? If so, go to next step. If not, then see DIAGNOSTIC STARTING POINT (HYDRAULIC BRAKE)  under TROUBLE SHOOTING.
  2. Visually inspect the disc brake pads for the following:
    • Lining thickness.
    • Uneven and/or abnormal wear (edge-to-edge and/or side-to-side).
    • Evidence of contamination from an external substance.
    • Looseness or damage (including pad hardware).
    Did you find any conditions to indicate a concern with any of the disc brake pads? If so, go to next step. If not, go to step  12 .
  3. Are any of the disc brake pads contaminated? If so, go to step  8 . If not, go to next step.
  4. Are any of the disc brake pads worn unevenly? If so, go to step  7 . If not, go to next step.
  5. Are any of the disc brake pads and/or pad hardware loose or damaged? If so, go to step  7 . If not, go to next step.
  6. Remove and inspect the worn disc brake pads for glazing, looseness, heat spots or damage. Replace the worn disc brake pads as a complete axle set. See FRONT BRAKE PADS  under REMOVAL & INSTALLATION. When finished, go to step  12 .
    7. NOTE: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.
  7. Perform the following:
    1. Remove the disc brake calipers (as appropriate) from the mounting brackets and support the calipers. Do Not disconnect the hydraulic brake flex hoses from the calipers. See FRONT BRAKE CALIPER  under REMOVAL & INSTALLATION.
    2. Inspect the disc brake caliper mounting bracket and the mounting/sliding hardware for the following conditions:
      • Loose, bent, cracked, or damaged caliper mounting bracket
      • Binding or seized hardware
      • Worn, damaged or missing hardware components
      See DISC BRAKE MOUNTING AND HARDWARE INSPECTION  under ADJUSTMENTS & INSPECTIONS.
    3. Replace components as required. Refer to the following procedures as required:
    4. Replace the unevenly-worn, loose or damaged disc brake pads as a complete axle set. See FRONT BRAKE PADS  under REMOVAL & INSTALLATION. When finished, go to step  12 .
  8. Inspect the disc brake calipers, brake hoses and brake pipes for evidence of an external brake fluid leak. Replace any components found to be leaking brake fluid. Refer to the following procedures as required: Did you find and correct the source of the leak causing contamination of the pads? If so, go to step  11 . If not, go to next step.
  9. Inspect the wheel drive shaft outer seals (boots) for damage and evidence of a grease leak. Replace any wheel drive shaft seal (boot) that is found to be leaking grease which may be the source of the contamination to the pads. See appropriate AXLE SHAFTS article in DRIVE AXLES. Did you find and correct the source of the leak causing contamination of the pads? If so, go to step  11 . If not, go to next step.
  10. Inspect the following systems for damage and evidence of an external fluid leak. Replace any components found to be leaking fluid which may be the source of the contamination to the pads. Refer to the following procedures:
    • See appropriate POWER STEERING article in STEERING.
    • See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSIONS.
    When finished, go to next step.
  11. Perform the following:
    • Clean the remaining disc brake system components to remove any traces of the contaminant.
    • Remove the disc brake calipers (as appropriate) from the mounting brackets and support the calipers. Do Not disconnect the hydraulic brake flex hoses from the calipers. See FRONT BRAKE CALIPER  under REMOVAL & INSTALLATION.
    • Inspect the disc brake caliper mounting/sliding hardware for the following conditions: Binding or seized hardware, Distorted, worn, damaged or missing hardware components. See DISC BRAKE MOUNTING AND HARDWARE INSPECTION  under ADJUSTMENTS & INSPECTIONS.
    • Replace the caliper mounting/sliding hardware components as required. See DISC BRAKE HARDWARE  under REMOVAL & INSTALLATION.
    • Replace the contaminated disc brake pads as a complete axle set. See FRONT BRAKE PADS  under REMOVAL & INSTALLATION.
    When finished, go to next step.
  12. Check the thickness of each of the disc brake rotors. Make a determination for each brake rotor if the rotor can be refinished and remain above the minimum requirements. See DISC BRAKE ROTOR THICKNESS MEASUREMENT  under TROUBLE SHOOTING. Does the disc brake rotor meet the minimum requirements for REFINISHING? If so, go to next step. If not, go to step  15 .
  13. Perform the following:
    • Inspect each of the disc brake rotors for heavy rust and/or pitting, cracks and/or heat spots or excessive blueing discoloration.
    • Inspect each of the disc brake rotors for deep or excessive scoring beyond maximum acceptable level, Lateral runout beyond maximum acceptable level or thickness variation beyond maximum acceptable level.
    • Make a determination for each brake rotor if the rotor requires refinishing based upon the results of the inspection. If the brake rotor exhibits any of the listed conditions, it requires refinishing. Does the brake rotor require REFINISHING? If so, go to next step. If not, go to step  18 .
  14. Refinish the brake rotor. See BRAKE ROTOR REFINISHING  in ADJUSTMENTS & INSPECTIONS. Inspect the brake rotor thickness. See DISC BRAKE ROTOR THICKNESS MEASUREMENT  under TROUBLE SHOOTING. Were you able to REFINISH the brake rotor within the minimum requirements? If so, go to step  18 . If not, go to step  17 .
  15. Is the brake rotor at or below the DISCARD requirements? If so, go to step  17 . If not, go to next step.
  16. Inspect each of the disc brake rotors for the following surface and wear conditions:
    • Heavy rust and/or pitting.
    • Cracks and/or heat spots.
    • Excessive blueing discoloration.
    • Deep or excessive scoring beyond maximum acceptable level.
    • Lateral runout beyond maximum acceptable level.
    • Thickness variation beyond maximum acceptable level.

    Make a determination for each brake rotor if the rotor requires refinishing based upon the results of the inspection. If the brake rotor exhibits any of the following conditions, it requires refinishing:

    • Rotor exhibits one or more of the Braking Surface Conditions listed previously.
    • Rotor is beyond the acceptable level in one or more of the Braking Surface Wear Conditions listed previously.
    Does the brake rotor require REPLACEMENT? If so, go to next step. If not, go to step  18 .

  17. Replace the brake rotor. See FRONT BRAKE ROTOR  under REMOVAL & INSTALLATION. When finished, go to next step.
  18. Install or connect components that were removed or disconnected during diagnosis. When finished, return to referencing procedure.
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