GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Chevy P12 Chassis 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Brake System Diagnosis

Belt Tension

When servicing any part of the brake system, check the power steering pump belt for improper belt tension or wear. The serpentine belt is not adjustable.

Power Steering Fluid Level

When servicing any part of the brake system, check the fluid level in the power steering fluid reservoir. Check the fluid level at regular intervals. Add fluid as needed. Refer to Fluid and Lubricant Recommendations .

Brake System Diagnosis

Symptom

Causes

Excessive Brake Pedal Travel
    • Leaking Brake Pipe, Hose, or Connection. Refer to Brake Pipe Replacement and Front Brake Hose Replacement and Rear Brake Hose Replacement .
    • Leaking Piston Seal. Refer to Brake Caliper Overhaul in Disc Brakes.
    • Leaking Master Cylinder. Refer to Master Cylinder Overhaul .
    • Contaminated or Improper Brake Fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Uneven Lining Wear. Replace or Correct. Refer to Brake Pad Inspection in Disc Brakes.
    • Improper Rotor Thickness Variation. Refer to Brake Rotor Thickness Variation Check in Disc Brakes.
    • Excessive Lateral Run-Out. Refer to Brake Rotor Lateral Runout Check
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .

Brake Pedal Travel Gradually Increases
    • Leaking Brake Pipe, Hose, or Connection. Refer to Seal Leak Diagnosis .
    • Leaking Piston Seal. Refer to Brake Caliper Overhaul in Disc Brakes.
    • Leaking Master Cylinder. Refer to Master Cylinder Overhaul .
    • Restricted Passage in Booster. Refer to Master Cylinder Overhaul .
    • Damaged Booster. Refer to Power Brake Booster Replacement .
    • Improper Rotor Thickness Variation. Refer to Brake Rotor Thickness Variation Check in Disc Brakes.
    • Excessive Lateral Run-Out. Refer to Brake Rotor Lateral Runout Check .
    • Restricted Brake Fluid Passage. Refer to Brake Hose and Pipe Diagnosis .

Excessive Brake Pedal Effort
    • Leaking Booster System. Refer to Power Brake Booster Replacement .
    • Restricted Passage in Booster. Refer to Power Brake Booster Replacement .
    • Damaged Booster. Refer to Power Brake Booster Replacement .
    • Worn Out Brake Lining. Replace. Refer to Brake Pad Inspection in Disc Brakes.
    • Glazed Brake Lining. Refer to Brake Pads Replacement in Disc Brakes.
    • Incorrect Brake Lining Material. Replace. Refer to Brake Pads Replacement in Disc Brakes.
    • Contaminated Brake Lining. Replace. Refer to Brake Pads Replacement in Disc Brakes.
    • Linings Damaged By Abusive Use. Replace. Refer to Brake Pads Replacement in Disc Brakes.
    • Restricted Brake Fluid Passage. Refer to Brake System Testing .
    • Brake Pedal Linkage Interference or Binding. Refer to Brake Pedal Travel .
    • Operator Riding the Brake Pedal. Refer to Brake Pad Inspection in Disc Brakes.
    • Rotor Surface Finish. Refer to Brake Rotor Refinishing in Disc Brakes.

Excessive Braking Action
    • Damaged Booster. Refer to Power Brake Booster Replacement .
    • Worn Out Brake Lining. Replace. Refer to Brake Pads Replacement in Disc Brakes.
    • Uneven Lining Wear. Replace or Correct. Refer to Brake Pads Replacement in Disc Brakes.
    • Incorrect Lining Material. Replace. Refer to Brake Pads Replacement in Disc Brakes.
    • Linings Damaged By Abusive Use. Replace. Refer to Brake Pads Replacement in Disc Brakes
    • Heat Spotted or Scored Discs. Refer to Brake Rotor Refinishing .
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .

Brakes Slow To Respond
    • Contaminated or Improper Brake Fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Leaking Booster System. Refer to Power Brake Booster Replacement .
    • Restricted Passage In Booster. Refer to Power Brake Booster Replacement .
    • Damaged Booster. Refer to Power Brake Booster Replacement .
    • Glazed Brake Lining. Refer to Brake Pads Replacement .
    • Restricted Brake Fluid Passage. Refer to Power Brake Booster Replacement .
    • Brake Pedal Linkage Interference or Binding. Refer to Brake Pedal Travel .
    • Sticking Caliper or Caliper Pistons. Refer to Brake Caliper Overhaul .

Brakes Slow To Release
    • Contaminated or Improper Brake Fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Restricted Passage in the Booster. Refer to Power Brake Booster Replacement .
    • Damaged Booster. Refer to Power Brake Booster Replacement .
    • Restricted Brake Fluid Passage. Refer to Power Brake Booster Replacement .
    • Brake Pedal Linkage Interference or Binding. Refer to Brake Pedal Travel .
    • Sticking Caliper or Caliper Pistons. Refer to Brake Caliper Overhaul .
    • Parking Brake not Releasing. Refer to Park Brake Cable Service/Adjustment .

Brakes Drag
    • Contaminated or Improper Brake Fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .
    • Restricted Brake Fluid Passage. Refer to Power Brake Booster Replacement .
    • Brake Pedal Linkage Interference or Binding. Refer to Brake Pedal Travel .
    • Improperly Adjusted Parking Brake. Refer to Parking Brake Shoe Adjustment .
    • Loose Front Suspension Attachments. Refer to Noise Diagnosis - Front Suspension .
    • Operator Riding Brake Pedal. Refer to Brake Pad Inspection .
    • Sticking Caliper or Caliper Pistons. Refer to Brake Caliper Overhaul .

Uneven Braking Action (Side to Side)
    • Contaminated or Improper Brake Fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Worn Out Brake Lining. Replace. Refer to Brake Pad Inspection .
    • Uneven Brake Wear. Replace or Correct. Refer to Brake Pads Replacement .
    • Glazed Brake Lining. Refer to Brake Pads Replacement .
    • Incorrect Brake Lining Material. Replace. Refer to Brake Pads Replacement .
    • Contaminated Brake Lining. Replace. Refer to Brake Pads Replacement .
    • Linings Damaged By Abusive Use. Refer to Brake Pads Replacement .
    • Heat Spotted or Scored Discs. Refer to Brake Rotor Refinishing .
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .
    • Restricted Brake Fluid Passage. Refer to Brake System Testing .
    • Improperly Adjusted Parking Brake. Refer to Parking Brake Shoe Adjustment .
    • Incorrect Front End Alignment. Refer to Front Camber Adjustment and Front Toe Adjustment .
    • Incorrect Tire Pressure. Refer to Tire Inflation Description .
    • Loose Front Suspension Attachments. Refer to Noise Diagnosis - Front Suspension .
    • Sticking Caliper or Caliper Pistons. Refer to Brake Caliper Overhaul .
    • Parking Brake not Releasing. Refer to Park Brake Cable Service/Adjustment .

Uneven Braking Action (Front to Rear)
    • Leaking Brake Pipe, Hose, or Connection. Refer to Brake Pipe Replacement and Master Cylinder Hose Replacement and Front Brake Hose Replacement or Rear Brake Hose Replacement .
    • Leaking Piston Seal. Refer to Brake Caliper Overhaul .
    • Leaking Master Cylinder. Refer to Master Cylinder Overhaul .
    • Contaminated or Improper Brake Fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Worn Out Brake Lining. Replace. Refer to Brake Pad Inspection .
    • Uneven Lining Wear. Replace or correct. Refer to Brake Pads Replacement .
    • Glazed Brake Lining. Refer to Brake Pads Replacement .
    • Incorrect Lining Material. Replace. Refer to Brake Pads Replacement .
    • Contaminated Brake Lining. Replace. Refer to Brake Pads Replacement .
    • Linings Damaged By Abusive Use. Replace. Refer to Brake Pads Replacement .
    • Heat Spotted or Scored Discs. Refer to Brake Rotor Refinishing .
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .
    • Restricted Brake Fluid Passage. Refer to Brake System Testing .
    • Improperly Adjusted Parking Brake. Refer to Parking Brake Shoe Adjustment .
    • Sticking Caliper or Caliper Pistons. Refer to Brake Caliper Overhaul .

Scraping Noise From Brakes
    • Worn Out Brake Lining. Replace. Refer to Brake Pad Inspection .
    • Uneven Lining Wear. Replace or Correct. Refer to Brake Pads Replacement .
    • Contaminated Brake Lining. Replace. Refer to Brake Pads Replacement .
    • Linings Damaged By Abusive Use. Replace. Refer to Brake Pads Replacement .
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .
    • Loose Front Suspension Attachments. Refer to Noise Diagnosis - Front Suspension .

Brakes Squeak During Application
    • Worn Out Brake Lining. Replace. Refer to Brake Pad Inspection .
    • Uneven Lining Wear. Replace or Correct. Refer to Brake Pads Replacement .
    • Glazed Brake Lining. Refer to Brake Pads Replacement .
    • Incorrect Lining Material. Replace. Refer to Brake Pads Replacement .
    • Contaminated Brake Lining. Replace. Refer to Brake Pads Replacement .
    • Linings Damaged by Abusive Use. Replace. Refer to Brake Pads Replacement .
    • Heat Spotted or Scored Discs. Refer to Brake Rotor Refinishing .

Brakes Squeak During Stop
    • Worn Out Brake Lining. Replace. Refer to Brake Pad Inspection .
    • Uneven Lining Wear. Replace or correct. Refer to Brake Pads Replacement .
    • Glazed Brake Lining. Refer to Brake Pads Replacement .
    • Incorrect Lining Material. Replace. Refer to Brake Pads Replacement .
    • Contaminated Brake Lining. Replace. Refer to Brake Pads Replacement .
    • Linings Damaged by Abusive Use. Refer to Brake Pads Replacement .
    • Heat Spotted or Scored Discs. Refer to Brake Rotor Refinishing .
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .

Brakes Chatter (Roughness)
    • Heat Spotted or Scored Discs. Refer to Brake Rotor Refinishing .
    • Improper Thickness Variation. Refer to Brake Rotor Thickness Variation Check .
    • Excessive Lateral Run-out. Refer to Brake Rotor Lateral Runout Check .
    • Brake Assembly Attachments Missing or Loose. Refer to Brake System Testing .

Brakes Groan At End Of Stop
    • Linings Damaged by Abusive Use. Refer to Brake Pads Replacement .
    • Loose Front Suspension Attachments. Refer to Noise Diagnosis - Front Suspension .
    • Out-of-Balance Wheel Assemblies. Refer to Wheel Alignment Specifications .

Brake Warning Lamp Glows
    • Leaking Brake Pipe, Hose, or Connection. Refer to Brake Pipe Replacement and Master Cylinder Hose Replacement and Front Brake Hose Replacement or Rear Brake Hose Replacement .
    • Leaking Piston Seal. Refer to Brake Caliper Overhaul .
    • Leaking Master Cylinder. Refer to Master Cylinder Overhaul .
    • Contaminated or Improper Brake Fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Worn Out Brake Lining. Replace. Refer to Brake Pad Inspection .
    • Uneven Lining Wear. Refer to Brake Pads Replacement .
    • Park Brake Switch Circuit Grounded. Refer to Stop Lamp Switch Replacement .
    • Parking Brake not Releasing. Refer to Park Brake Cable Service/Adjustment .