English
Uneven wear of brake pads not only shortens their service life, but may also lead to brake deviation, abnormal noise, and even brake failure. The following are systematic analysis and professional solutions:
1、 Mechanical reasons (accounting for over 70% of failures)
1. Poor lubrication of caliper guide pin
Phenomenon: One side brake pads are significantly thinner (thickness difference between inner and outer pads>2mm)
Principle: Rust on the guide pin causes the brake pads to fail to return to their normal position, resulting in continuous friction
Solution:
Remove the guide pin and lubricate it with specialized silicone grease (do not use regular butter)
Replace deformed/aged dust covers
2. Brake cylinder malfunction
High risk signals:
Brake oil leakage
Slow piston return (requires professional tools for testing)
Handling method:
Replace the cylinder repair kit (including sealing ring)
When severely stuck, the entire sub pump needs to be replaced (cost approximately 400-1200 yuan)
3. Brake disc deformation (DTV exceeding the standard)
Testing standards:
Measure with a dial gauge, if the axial runout is greater than 0.05mm, a disc or replacement is required
Cause:
Wash the car immediately after sudden braking due to high temperature
Long term brake overheating (common in mountainous driving)
2、 Installation issues (accounting for 20% of failures)
4. Reverse installation of brake pads
Typical case:
Abnormal wear caused by incorrect orientation of the alarm iron plate
Vibration wear caused by missing shock-absorbing pads (shim)
5. Poor quality brake pads with uneven backboards
Identification method:
Use a ruler to check the flatness of the backboard. If the error is greater than 0.2mm, it is considered unqualified
Consequences:
Causing local contact stress concentration and forming "step like wear"
3、 Chassis system impact (accounting for 10% of faults)
6. Abnormal suspension system
Related components:
Shock absorber failure (body nodding during braking exacerbates unilateral wear)
Swing arm rubber sleeve cracking (changing wheel alignment parameters)
Diagnostic process:
First, perform four-wheel alignment (adjust if there is an abnormal caster angle of the main pin)
Check the gap between the suspension connecting rods
7. Brake fluid issues
Key impacts:
Moisture content greater than 3% leads to corrosion and blockage of the pump
Long term non replacement leads to a decrease in boiling point, and air resistance affects the distribution of braking force
Maintenance standards:
Replace DOT4 brake fluid every 2 years or 40000 kilometers
Measure moisture content using a detection pen
4、 Wear and tear under extreme working conditions
8. Track/high-intensity driving
Special wear mode:
Carbonization and detachment of friction materials (appearance of glassy luster on the surface)
High temperature causes adhesive failure
Response plan:
Switch to competitive grade brake pads (such as Endless MX72)
Install brake air duct
Comparison Table of Wear Types
Root cause solution for wear morphology
Inner thin outer thick caliper guide pin stuck lubrication/replace guide pin
Wave shaped wear of uneven thickness of brake discs (DTV) disc or replacement of brake discs
Edge step wear brake pads not chamfered/backplate deformed, replace with qualified brake pads
The middle depression is worn and the piston of the cylinder cannot fully return to its original position for maintenance or replacement of the cylinder
Suggestions for professional testing tools
Dial gauge (detects brake disc runout)
Infrared thermometer (comparing the temperature difference between the two brake systems)
Brake fluid moisture content detection pen (<3% is qualified)
Maintenance cost reference
Maintenance project: Economy car cost, luxury car cost
Guided sales maintenance costs 80-150 yuan and 200-400 yuan
Single side cylinder replacement costs 300-600 yuan and 800-2000 yuan
Brake disc discs 100-200 yuan/pair 300-600 yuan/pair
Very preventive advice
Check the thickness of brake pads every 10000 kilometers (measured with a measuring tool)
Replace brake fluid and lubricate guide pins every 2 years
Avoid:
Immediately park for a long time after washing the car (which can easily cause rusting and adhesion of the brake disc)
Continuous light braking and drainage after wading through water
Important reminder: If one side of the brake pad is found to be thinner than the other by more than 30%, it must be repaired immediately! This may be a warning signal that the braking system is about to fail.
