Guide To Brake Problems
| Problem | Probable Cause | Corrective Action |
|---|
Low/Spongy Pedal |
Pedal nearly touches floorboard before brakes function. No brake reserve. |
No fluid in master cylinder. | Check system for fluid leak and repair. |
| Excessive free play in brake pedal linkage. | Adjust for proper linkage. | ||
| Pad "knock-back". | Examine rotor run out and parallelism, bearing adjustment, etc. | ||
| Excessive clearance between linings and drums. | Adjust brakes. | ||
| Contaminated fluid. | Replace with approved brake fluid. | ||
| Residual line pressure valve faulty | Check/replace | ||
| Air in hydraulic system. | Bleed brake system. |
High Pedal Force |
Excessive stopping distance, excessive pedal effort, brakes do not react properly. | Worn/glazed pads or linings. | Replace with new pads or linings. |
| Frozen calipers or wheel cylinders. | Free up and replace if necessary. | ||
| Brake booster failure | Inspect booster Assy. Repair as required |
Brake Drag |
Sticking brakes may be failing to release properly. | Brakes adjusted too tight. | Readjust and allow sufficient clearance between lining and drum. |
| Master cylinder by-pass port blocked. | Clear blockage. | ||
| Weak pedal return spring. | Install new springs. | ||
| Distorted backing plates. | Replace with new plates. | ||
| Sticky wheel cylinder. | Repair with new cups. |
Brake Pull |
Car pulls to one side when brakes are applied. | Contamination of pads or linings with brake fluid, oil, grease, etc. | Clean or replace pads or linings. |
| Unmatched pads or linings. | Replace with correct parts. | ||
| Faulty caliper pad alignment. | Check for loose caliper mounting bolts, guide pins, broken clips. | ||
| Unequal brake adjustment. | Readjust all brakes. | ||
| Seized Calliper. | Overhaul both calipers (ie. pin and seal kits) on that axle. |
Brake Grab |
"Touchy" brakes that grab with least pressure. | Contamination of pads or linings with brake fluid, oil, grease, etc. | Clean or replace pads or linings. |
| Caliper not aligned with disc. | Correct alignment. | ||
| Mounting bolts loose. | Tighten to specified torque. | ||
| Brake lines, hoses kinked, collapsed or clogged. | Repair or replace. | ||
| Caliper pistons or slides seized. | Free up and replace if damaged. |
Brake Noise |
Brakes should operate with minimal amount of noise. However excessive squeal, screech, groaning, grinding chatter or rattle means your brakes need attention. |
Too much lateral run out of rotor. | Correct runout to manufacturers spec. |
| Worn pads or linings. | Replace with new pads or linings. | ||
| Twisted brake shoe. | Replace brake shoes. | ||
| Weak or broken spring components. | Replace with new springs. | ||
| Drums out of round. | Turn or replace drums. | ||
| Loose wheel bearing. | Adjust or replace faulty parts. | ||
| Foreign particles embedded in material. | Replace with new pads or linings. | ||
| Faulty caliper alignment. | Readjust. |
Vibration |
Brake pedal, steering wheel or entire wheel shakes, vibrates or pulsates when brake is applied. | Rotor run out and parallelism. | Resurface disc brake rotors. |
| Wear in steeringand suspension components. | Examine and replace worn components. | ||
| Wheels out of balance. | Wheel balance required. |
Brake Wear |
Premature wear can be caused by a number of faults in the brake system. To avoid costly repairs have the brakes checked at least once a year. |
Wrong type of pad or lining material for operating conditions. | Replace with correct pad or lining material for application. |
| Caliper pistons and/or pins seized. | Fit pin and seal kits. | ||
| Extremely rough rotor surface. | Regrind rotors. |