Brake System Diagnosis. Chevrolet Astro

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 1998 🢒 Astro - 4WD 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Brake System Diagnosis

Symptom

Causes

Excessive brake pedal travel

•	Leaking brake pipe, hose, or connection. Refer to Brake Fluid Leak .

•	Leaking piston seal. Refer to Seal Leak Diagnosis .

•	Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis .

•	Air in brake system. Refer to Hydraulic Brake System Bleeding .

•	Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

•	Improper thickness variation. Refer to Brake Rotor Thickness Variation Check in Disc Brakes, or Brake Drum Inspection in Drum Brakes.

•	Uneven brake lining wear. Refer to Brake Pad Inspection in Disc Brakes, or to Brake Shoe Inspection in Drum 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, or Brake Shoe Inspection in Drum Brakes.

Brake pedal travel gradually increases

•	Leaking brake pipe, hose, or connection. Refer to Brake Fluid Leak .

•	Leaking piston seal. Refer to Seal Leak Diagnosis .

•	Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis .

•	Improper thickness variation. Refer to Brake Rotor Thickness Variation Check in Disc Brakes, or Brake Drum Inspection in Drum Brakes.

•	Excessive lateral run-out. Refer to Brake Rotor Lateral Runout Check in Disc Brakes.

•	Restricted brake fluid passage. Refer to Hydraulic Brake System Bleeding .

Excessive brake pedal effort

•	Worn out brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Glazed brake lining.

•	Incorrect brake lining material. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Contaminated brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Linings damaged by abuse. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Restricted brake fluid passage. Refer to Hydraulic Brake System Bleeding .

•	Brake pedal or brake linkage interference (binding). Refer to Brake Pedal Replacement .

•	Operator riding the brake pedal.

•	Rotor or drum surface finish. Refer to Brake Rotor Refinishing in Disc Brakes and Brake Drum Refinishing in Drum Brakes.

Excessive braking action

•	Worn out brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Uneven brake lining wear. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Incorrect brake lining material. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Brake lining damage by abuse. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Heat spotted or scored discs. Refer to Brake Rotor Tolerance in Disc Brakes.

•	Brake assembly attachments missing or loose. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

Brakes slow to respond

•	Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

•	Glazed brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Restricted brake fluid passage. Refer to Hydraulic Brake System Bleeding .

•	Brake pedal or brake linkage interference (binding). Refer to Brake Pedal Replacement .

•	Sticking caliper or caliper pistons. Refer to Brake Caliper Inspection .

Brakes slow to release

•	Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

•	Restricted brake fluid passage. Refer to Hydraulic Brake System Bleeding .

•	Brake pedal or brake linkage interference (Binding). Refer to Brake Pedal Replacement .

•	Sticking caliper or caliper pistons. Refer to Brake Caliper Inspection in Disc Brakes.

•	Park brake not releasing. Refer to Park Brake Cable Service/Adjustment in Park Brake.

Brakes drag

•	Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

•	Brake assembly attachments missing or loose. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Restricted brake fluid passage. Refer to Hydraulic Brake System Bleeding .

•	Brake pedal or brake linkage interference (Binding). Refer to Brake Pedal Replacement .

•	Improperly adjusted park 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 Brake Caliper Inspection .

Uneven braking action (side to side)

•	Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

•	Worn out brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Uneven brake lining wear. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Glazed brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Incorrect brake lining material. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Contaminated brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Brake lining damage by abuse. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Heat spotted or scored discs. RefeIP Cluster ReplacementIP Cluster Replacementr to Brake Rotor Tolerance .

•	Brake assembly attachments missing or loose. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Restricted brake fluid passage. Refer to Hydraulic Brake System Bleeding .

•	Improperly adjusted park brake. Refer to Park Brake Cable Service/Adjustment in Park Brake.

•	Incorrect front end alignment. Refer to Wheel Alignment Measurement .

•	Incorrect tire pressure. Refer to Tire Inflation Pressure Specifications.

•	Loose front suspension attachments. Refer to Fastener Tightening Specifications in Front Suspension.

•	Sticking caliper or caliper pistons. Refer to Brake Caliper Inspection .

•	Park 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 .

•	Leaking piston seal. Refer to Seal Leak Diagnosis .

•	Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis .

•	Air in brake system. Refer to Hydraulic Brake System Bleeding .

•	Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

•	Worn out brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Uneven lining wear. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Glazed brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Incorrect brake lining material. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Contaminated brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Linings damaged by abusive use. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Heat spotted or scored discs. Refer to Brake Rotor Tolerance .

•	Brake assembly attachments missing or loose. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Restricted brake fluid passage. Refer to Hydraulic Brake System Bleeding .

•	Improperly adjusted park brake. Refer to Park Brake Cable Service/Adjustment in Park Brake.

•	Sticking caliper or caliper pistons. Refer to Brake Caliper Inspection .

Scraping noise from brakes

•	Worn out brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Uneven lining wear. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Contaminated brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Linings damaged by abusive use. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Brake assembly attachments missing or loose. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum 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, or Brake Shoe Inspection in Drum Brakes.

•	Uneven brake lining wear. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Glazed brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Incorrect brake lining material. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Contaminated brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Brake lining damage by abuse. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Heat spotted or scored rotors. Refer to Brake Rotor Tolerance .

Brakes squeak during application

•	Worn out brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Uneven brake lining wear. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Glazed brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Incorrect brake lining material. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Contaminated brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Linings damaged by abusive use. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Heat spotted or scored discs. Refer to Brake Rotor Tolerance .

Binding hydroboost spool valve

Contaminated power steering fluid. Refer to Power Steering System Flushing in Power Steering Gear and Pump.

Brakes chatter (roughness)

•	Heat spotted or scored discs. Refer to Brake Rotor Tolerance .

•	Improper thickness variation. Refer to Brake Rotor Thickness Variation Check in Disc Brakes, or Brake Drum Inspection in Drum Brakes.

•	Excessive lateral runout. Refer to Brake Rotor Lateral Runout Check .

•	Brake assembly attachments missing or loose. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

Brakes groan at end of stop

Linings damaged by abuse. Refer to Brake Rotor Thickness Variation Check in Disc Brakes or Brake Drum Inspection in Drum Brakes.
Loose front suspension attachments. Refer to Fastener Tightening Specifications in Front Suspension.
Out of balance wheel assemblies. Refer to Tire and Wheel Balancing in Vibration Diagnosis and Correction.

Brake warning lamp ON

•	Leaking brake pipe, hose, or connection. Refer to Brake Fluid Leak .

•	Leaking piston seal. Refer to Seal Leak Diagnosis .

•	Leaking master cylinder (internal). Refer to Master Cylinder Diagnosis .

•	Air in brake system. Refer to Hydraulic Brake System Bleeding .

•	Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .

•	Worn out brake lining. Refer to Brake Pad Inspection in Disc Brakes, or Brake Shoe Inspection in Drum Brakes.

•	Uneven lining wear. Refer to Brake Rotor Thickness Variation Check in Disc Brakes, or Brake Drum Inspection in Drum Brakes.

•	Park brake switch circuit grounded.

•	Park brake not releasing. Refer to Park Brake Cable Service/Adjustment in Park Brake.