Pad Contamination
APPEARANCE
Friction material is contaminated with either oil, grease or brake fluid
CAUSE
Spillage during maintenance, or fluid that has leaked from the caliper
EFFECT
- The vehicle pulls to one side during braking
- Reduction in braking performance
REMEDY
- Identify and repair cause of contamination
- Replace the brake pad set
Glazing
APPEARANCE
The brake pad friction material is glazed
CAUSE
- High intermittent pad temperature over short time periods
- Overly harsh braking during the bedding-in period
EFFECT
Temporary reductions in brake performance
REMEDY
- If light glazing is evident, no action is required
- If heavy glazing is evident, replace brake pad set
- Check the rotor condition
Uneven Wear - Wear Lip
APPEARANCE
Uneven wear on the pad surface
CAUSE
An irregularly worn rotor or "wear lip" on the rotor will cause this pattern of wear on the brake pad
EFFECT
- Squeal and judder
- Premature pad wear
REMEDY
Replace brake rotors and pads
Back Plate Damage
APPEARANCE
Damaged back plate
CAUSE
Incorrect assembly, or excessive force used during fitting
EFFECT
- Braking efficiency
- Irregular pad wear
- Noise & judder
REMEDY
Replace the brake pad set
Uneven Wear Within A Set
APPEARANCE
One or more brake pads within an axle set is excessively worn
CAUSE
Caliper guide pins or piston is sticking
EFFECT
- Brake pulls to one side
- Uneven & overly rapid pad wear
REMEDY
- Maintain all caliper slides and pistons
- Replace pads and check replace discs if necessary
Rusty Pads
APPEARANCE
Rust between the friction material and back plate
CAUSE
A brake pad sticking in the caliper bracket when braking flexes the back plate, cracking the friction material. Corrosion worsens this, separating the friction material and back plate.
EFFECT
- Noise and soft pedal feel
- Once material has separated, brakes will not work
REMEDY
- Replace brake pad set
- Clean and maintain caliper to ensure the pad fits freely into the caliper during installation
Tapered Pads
APPEARANCE
Uneven wear or tapered pads
CAUSE
- Caliper is distorted and the caliper slides are sticking
- Excessive caliper clearance
EFFECT
- Premature pad wear and noise while braking
- Uneven braking pressure
REMEDY
Replace pad set and maintain & service caliper
Note: Some vehicles use pads that are tapered by design. Refer to vehicle application to determine if they are outside normal degree of taper.
Incorrect Pad Fitting
APPEARANCE
Damaged pads
CAUSE
- These "handed" pads are not identical to each other within the set, and need to be fitted to either the inner or outer side of the caliper
- When fitted incorrectly, the pads will be damaged
EFFECT
- Damaged pads
- Reduced brake performance
REMEDY
Replace pad set to manufacturer's instructions as per the inserted diagram
Uneven Wear - Disc Scoring
APPEARANCE
Uneven wear pattern on the pad
CAUSE
- Incomplete contact between brake pad and rotor
- Rotor scoring due to dust or excessive wear
- New pads fitted to a worn rotor may also cause this
EFFECT
- Squeal and judder
- Braking efficiency
REMEDY
Replace both brake pads and rotors
Denaturing
APPEARANCE
Partially charred or burnt friction material (will show whitish outer edges)
CAUSE
Prolonged excessive pad temperature due to intensive use or dragging of the brake pad on the rotor
EFFECT
- Reduction in initial brake efficiency
- Excessive material deterioration and abnormal wear
- Material becomes brittle, chips and cracks
REMEDY
- Investigate cause for overheating of brake pad
- If damage is not excessive, pads will be effective under normal use
- If the damage is extensive replace brake pad set
Cracked Pads
APPEARANCE
Small cracks in the centre of the pad
CAUSE
The cracks indicate that the caliper is sticking. The piston bends the back plate causing the back plate to flex, cracking the friction material.
EFFECT
- Noise while braking
- Uneven pad wear
- Vehicle pulling to one side during braking
- Overheating on one side of the vehicle
REMEDY
- Maintain and service the caliper
- Replace the brake pad set
Edge Crumbling
APPEARANCE
Uneven wear pattern on the pad
CAUSE
Brake pad is sticking within the caliper causing the brake pad to stay in contact with the rotor with associated excessive pad temperature
EFFECT
Pad surface may glaze reducing brake performance
REMEDY
- Investigate cause of caliper sticking
- Maintain the caliper
- Replace the brake pad set
Worn Out Pads
APPEARANCE
Friction material is completely worn out
CAUSE
There has been no regular check of pad wear or proper brake maintenance
EFFECT
- Vehicle pulls to one side during braking
- Damage to the disc
- High squeal and other brake noise
REMEDY
- Check the disc for damage
- Replace pad set and the rotor if it has suffered damage
METAL PICK UP / RESIDUE
APPEARANCE
Metal pick-up (or ingrained metal) on the friction surface
CAUSE
During normal braking small particles of the rotor surface break off. Typically these are burnt off by the intense heat as dust. During extremely wet conditions these are quenched, cooled fast to solid material, and adhere to the brake pad surface.
EFFECT
This generally has no detrimental effect on braking performance, however in extreme cases, it can cause disc damage or brake squeal
REMEDY
In extreme cases, replace discs and pads
Pad Contamination
APPEARANCE
Friction material is contaminated with either oil, grease or brake fluid
CAUSE
Spillage during maintenance, or fluid that has leaked from the caliper
EFFECT
- The vehicle pulls to one side during braking
- Reduction in braking performance
REMEDY
- Identify and repair cause of contamination
- Replace the brake pad set
Glazing
APPEARANCE
The brake pad friction material is glazed
CAUSE
- High intermittent pad temperature over short time periods
- Overly harsh braking during the bedding-in period
EFFECT
Temporary reductions in brake performance
REMEDY
- If light glazing is evident, no action is required
- If heavy glazing is evident, replace brake pad set
- Check the rotor condition
Uneven Wear - Wear Lip
APPEARANCE
Uneven wear on the pad surface
CAUSE
An irregularly worn rotor or "wear lip" on the rotor will cause this pattern of wear on the brake pad
EFFECT
- Squeal and judder
- Premature pad wear
REMEDY
Replace brake rotors and pads
Back Plate Damage
APPEARANCE
Damaged back plate
CAUSE
Incorrect assembly, or excessive force used during fitting
EFFECT
- Braking efficiency
- Irregular pad wear
- Noise & judder
REMEDY
Replace the brake pad set
Uneven Wear Within A Set
APPEARANCE
One or more brake pads within an axle set is excessively worn
CAUSE
Caliper guide pins or piston is sticking
EFFECT
- Brake pulls to one side
- Uneven & overly rapid pad wear
REMEDY
- Maintain all caliper slides and pistons
- Replace pads and check replace discs if necessary
Rusty Pads
APPEARANCE
Rust between the friction material and back plate
CAUSE
A brake pad sticking in the caliper bracket when braking flexes the back plate, cracking the friction material. Corrosion worsens this, separating the friction material and back plate.
EFFECT
- Noise and soft pedal feel
- Once material has separated, brakes will not work
REMEDY
- Replace brake pad set
- Clean and maintain caliper to ensure the pad fits freely into the caliper during installation
Tapered Pads
APPEARANCE
Uneven wear or tapered pads
CAUSE
- Caliper is distorted and the caliper slides are sticking
- Excessive caliper clearance
EFFECT
- Premature pad wear and noise while braking
- Uneven braking pressure
REMEDY
Replace pad set and maintain & service caliper
Note: Some vehicles use pads that are tapered by design. Refer to vehicle application to determine if they are outside normal degree of taper.
Incorrect Pad Fitting
APPEARANCE
Damaged pads
CAUSE
- These "handed" pads are not identical to each other within the set, and need to be fitted to either the inner or outer side of the caliper
- When fitted incorrectly, the pads will be damaged
EFFECT
- Damaged pads
- Reduced brake performance
REMEDY
Replace pad set to manufacturer's instructions as per the inserted diagram
Uneven Wear - Disc Scoring
APPEARANCE
Uneven wear pattern on the pad
CAUSE
- Incomplete contact between brake pad and rotor
- Rotor scoring due to dust or excessive wear
- New pads fitted to a worn rotor may also cause this
EFFECT
- Squeal and judder
- Braking efficiency
REMEDY
Replace both brake pads and rotors
Denaturing
APPEARANCE
Partially charred or burnt friction material (will show whitish outer edges)
CAUSE
Prolonged excessive pad temperature due to intensive use or dragging of the brake pad on the rotor
EFFECT
- Reduction in initial brake efficiency
- Excessive material deterioration and abnormal wear
- Material becomes brittle, chips and cracks
REMEDY
- Investigate cause for overheating of brake pad
- If damage is not excessive, pads will be effective under normal use
- If the damage is extensive replace brake pad set
Cracked Pads
APPEARANCE
Small cracks in the centre of the pad
CAUSE
The cracks indicate that the caliper is sticking. The piston bends the back plate causing the back plate to flex, cracking the friction material.
EFFECT
- Noise while braking
- Uneven pad wear
- Vehicle pulling to one side during braking
- Overheating on one side of the vehicle
REMEDY
- Maintain and service the caliper
- Replace the brake pad set
Edge Crumbling
APPEARANCE
Uneven wear pattern on the pad
CAUSE
Brake pad is sticking within the caliper causing the brake pad to stay in contact with the rotor with associated excessive pad temperature
EFFECT
Pad surface may glaze reducing brake performance
REMEDY
- Investigate cause of caliper sticking
- Maintain the caliper
- Replace the brake pad set
Worn Out Pads
APPEARANCE
Friction material is completely worn out
CAUSE
There has been no regular check of pad wear or proper brake maintenance
EFFECT
- Vehicle pulls to one side during braking
- Damage to the disc
- High squeal and other brake noise
REMEDY
- Check the disc for damage
- Replace pad set and the rotor if it has suffered damage
METAL PICK UP / RESIDUE
APPEARANCE
Metal pick-up (or ingrained metal) on the friction surface
CAUSE
During normal braking small particles of the rotor surface break off. Typically these are burnt off by the intense heat as dust. During extremely wet conditions these are quenched, cooled fast to solid material, and adhere to the brake pad surface.
EFFECT
This generally has no detrimental effect on braking performance, however in extreme cases, it can cause disc damage or brake squeal
REMEDY
In extreme cases, replace discs and pads