GM Service Manual Online
For 1990-2009 cars only

Symptom

Causes

Excessive Brake Pedal Travel

    • Leaking brake pipe, hose, or connection. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking piston seal. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis in Hydraulic Brakes.
    • Air in brake system. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling in Hydraulic Brakes.
    • Improper thickness variation. Refer to Brake Rotor Thickness Variation Check in Disc Brakes.
    • Uneven brake lining wear. Refer to Brake Pad Inspection in Disc Brakes.
    • Excessive lateral runout. Refer to Brake Rotor Lateral Runout Check in Disc Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes .

Brake Pedal Travel Gradually Increases

    • Leaking brake pipe, hose, or connection. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking piston seal. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis in Hydraulic Brakes.
    • Restricted Passage in the Vacuum Booster. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Damaged Vacuum Booster System. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Restricted Brake Fluid Passage. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.

Excessive Brake Pedal Effort

    • Leaking Vacuum Booster System. Refer to Vacuum Brake Booster Check Valve Replacement in Hydraulic Brakes.
    • Restricted Passage in the Vacuum Booster. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Damaged Vacuum Booster System. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Worn Out Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Glazed Brake Lining. Refer to latest bulletin.
    • Incorrect Brake Lining Material. Refer to Brake Pad Inspection in Disc Brakes .
    • Contaminated Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake lining Damage By Abuse. Refer to Brake Pad Inspection in Disc Brakes .
    • Restricted Brake Fluid Passage. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Brake Pedal or Brake Linkage Interference (Binding). Refer to Brake Pedal Replacement in Hydraluic Brakes.
    • Operator Riding the Brake Pedal.

Excessive Braking Action

    • Damaged Vacuum Booster System. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Worn Out Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Uneven brake lining wear. Refer to Brake Pad Inspection in Disc Brakes.
    • Incorrect Brake Lining Material. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake lining Damage By Abuse. Refer to Brake Pad Inspection in Disc Brakes.
    • Rotor Surface or Drum Surface Finish. Refer to Brake Rotor Refinishing in Disc Brakes.
    • Heat Spotted or Scored Rotors. Refer to Brake Rotor Tolerance in Disc Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes.

Brakes Slow To Respond

    • Contaminated or improper brake fluid. Refer to Hydraulic Brake System Flushing in Hydraulic Brakes.
    • Leaking Vacuum System. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Restricted Passage in the Vacuum Booster. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Damaged Vacuum Booster System. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Glazed Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Restricted Brake Fluid Passage. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Brake Pedal or Brake Linkage Interference (Binding). Refer to Brake Pedal Replacement in Hydraulic Brakes.
    • Sticking Caliper or Caliper Pistons. Refer to Front Brake Caliper Overhaul in Disc Brakes.

Brakes Slow To Release

    • Contaminated or improper brake fluid. Refer to Hydraulic Brake System Flushing in Hydraulic Brakes.
    • Restricted Passage in the Vacuum Booster. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Damaged Vacuum Booster System. Refer to Vacuum Booster Diagnosis in Hydraulic Brakes.
    • Restricted Brake Fluid Passage. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Brake Pedal or Brake Linkage Interference (Binding). Refer to Brake Pedal Replacement in Hydraulic Brakes.
    • Sticking Caliper or Caliper Pistons. Refer to Front Brake Caliper Overhaul in Disc Brakes.
    • Parking Brake not Releasing. Refer to Park Brake Cable Service/Adjustment in Park Brake.

Brakes Drag

    • Contaminated or improper brake fluid. Refer to Hydraulic Brake System Flushing in Hydraulic Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes.
    • Restricted Brake Fluid Passage. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Brake Pedal or Brake Linkage Interference (Binding). Refer to Brake Pedal Replacement in Hydraulic Brakes.
    • Improperly Adjusted Parking Brake. Refer to Park Brake Cable Service/Adjustment in Park Brake.
    • Loose Front Suspension Attachments. Refer to Fastener Tightening Specifications in Front Suspension.
    • Operator Riding the Brake Pedal.
    • Sticking Caliper or Caliper Pistons. Refer to Front Brake Caliper Overhaul in Disc Brakes.

Uneven Braking Action (Side to Side)

    • Contaminated or improper brake fluid. Refer to Hydraulic Brake System Flushing in Hydraulic Brakes.
    • Worn Out Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Uneven Brake Lining Wear. Refer to Brake Pad Inspection in Disc Brakes.
    • Glazed Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Incorrect Brake Lining Material. Refer to Brake Pad Inspection in Disc Brakes.
    • Contaminated Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake lining Damage By Abuse. Refer to Brake Pad Inspection in Disc Brakes.
    • Heat Spotted or Scored Rotors. Refer to Brake Rotor Tolerance in Disc Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes.
    • Restricted Brake Fluid Passage. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Incorrect Front End Alignment. Refer to Wheel Alignment Specifications in Wheel Alignment.
    • Incorrect Tire Pressure. Refer to Tire Inflation Description in Tires and Wheels.
    • Loose Front Suspension Attachments. Refer to Fastener Tightening Specifications in Front Suspension.
    • Sticking Caliper or Caliper Pistons. Refer to Front Brake Caliper Overhaul in Disc Brakes.
    • Parking Brake Not Releasing. Refer to Park Brake Cable Service/Adjustment in Park Brake.

Uneven Braking Action (Front to Rear)

    • Leaking brake pipe, hose, or connection. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking piston seal. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis in Hydraulic Brakes.
    • Air in brake system. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Contaminated or improper brake fluid. Refer to Hydraulic Brake System Flushing in Hydraulic Brakes.
    • Worn Out Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Uneven Brake Lining Wear. Refer to Brake Pad Inspection in Disc Brakes.
    • Glazed Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Incorrect Brake Lining Material. Refer to Brake Pad Inspection in Disc Brakes.
    • Contaminated Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake lining Damage By Abuse. Refer to Brake Pad Inspection in Disc Brakes.
    • Heat Spotted or Scored Rotors. Refer to Brake Rotor Tolerance in Disc Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes.
    • Restricted Brake Fluid Passage. Refer to Hydraulic Brake System Bleeding in Hydraulic Brakes.
    • Improperly Adjusted Parking Brake. Refer to Park Brake Cable Service/Adjustment in Park Brake.
    • Sticking Caliper or Caliper Pistons. Refer to Front Brake Caliper Overhaul in Disc Brakes.

Scraping Noise From Brakes

    • Worn Out Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Uneven Brake Lining Wear. Refer to Brake Pad Inspection in Disc Brakes.
    • Contaminated Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake lining Damage By Abuse. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes.
    • Loose Front Suspension Attachments. Refer to Fastener Tightening Specifications in Front Suspension

Brakes Squeak Without Application

    • Worn Out Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Uneven Brake Lining Wear. Refer to Brake Pad Inspection in Disc Brakes.
    • Glazed Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Incorrect Brake Lining Material. Refer to Brake Pad Inspection in Disc Brakes.
    • Contaminated Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake Lining Damage By Abuse. Refer to Brake Pad Inspection in Disc Brakes.
    • Heat Spotted or Scored Rotors. Refer to Brake Rotor Tolerance in Disc Brakes.

Brakes Squeak During Application

    • Worn Out Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Uneven Brake Lining Wear. Refer to Brake Pad Inspection in Disc Brakes.
    • Glazed Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Incorrect Brake Lining Material. Refer to Brake Pad Inspection in Disc Brakes.
    • Contaminated Brake Lining. Refer to Brake Pad Inspection in Disc Brakes.
    • Brake lining Damage By Abuse. Refer to Brake Pad Inspection in Disc Brakes.
    • Heat Spotted or Scored Rotors. Refer to Brake Rotor Tolerance in Disc Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes.

Brakes Chatter (Roughness)

    • Heat Spotted or Scored Rotors. Refer to Brake Rotor Tolerance in Disc Brakes.
    • Improper thickness variation. Refer to Brake Rotor Thickness Variation Check in Disc Brakes.
    • Excessive lateral runout. Refer to Brake Rotor Lateral Runout Check in Disc Brakes.
    • Brake Assembly Attachments Missing or Loose. Refer to Brake Pad Inspection in Disc Brakes.
    • Loose Front Suspension Attachments. Refer to Fastener Tightening Specifications in Front Suspension.
    • Out-Of-Balance Wheel Assemblies. Refer to Balancing Tires and Wheels in Vibration Diagnosis.

Brakes Groan At End Of Stop

Brake lining Damage By Abuse. Refer to Brake Rotor Thickness Variation Check in Disc Brakes.

Brake Warning Lamp ON

    • Leaking brake pipe, hose, or connection. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking piston seal. Refer to Brake Fluid Leak in Hydraulic Brakes.
    • Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis in Hydraulic Brakes.
    • Air in brake system. Refer to Hydraulic Brake System Bleeding .
    • Contaminated or improper brake fluid. Refer to Hydraulic Brake System Flushing in Hydraulic Brakes.
    • Uneven Brake Lining Wear. Refer to Brake Rotor Thickness Variation Check in Disc Brakes.
    • Park Brake Switch Circuit Grounded.
    • Parking Brake not Releasing. Refer to Park Brake Cable Service/Adjustment in Park Brake.
    • Low Brake Fluid. Refer to Master Cylinder Reservoir Filling in Hydraulic Brakes.