Brake Pad Contamination
Brake pad contamination from grease, brake fluid, gear oil, or other fluid can cause pulling, grabbing, noise, or weak braking.
Can I Drive?
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Most Likely Causes
- 1
Brake fluid leak onto pads
Leaking caliper or wheel cylinder fluid soaks friction material.
- 2
Grease or anti-seize on friction surface
Lubricant placed in the wrong location contaminates pads.
- 3
Axle or hub seal leak
Gear oil or grease can reach brakes on some designs.
- 4
Road chemical or debris contamination
Heavy contamination can change friction on one side.
How to Diagnose It
- 1
Inspect pads and rotor surface
Look for oily, wet, shiny, or uneven friction surfaces.
Tool: Wheel removal tools
- 2
Find the source of contamination
Check caliper seals, axle seals, and hardware lubricant placement.
Tool: Flashlight
- 3
Compare side-to-side braking behavior
Contaminated pads often pull or grab differently than the other side.
Tool: Safe test area
How to Fix It
Repair leak source first
Fix the caliper, wheel cylinder, or axle seal before installing new pads.
Replace contaminated pads
Friction material soaked with fluid should be replaced.
Clean or replace rotors as needed
Clean light surface residue; replace rotors if badly saturated or damaged.
Mistakes to Avoid
- Do not try to save pads soaked with brake fluid or gear oil.
- Do not apply grease to pad friction material or rotor faces.
- Do not replace pads before repairing the leak that contaminated them.