Replace brake pads/linings when thickness reaches the manufacturer’s minimum limit, when wear indicators are triggered (if equipped), or when performance becomes inconsistent even after proper adjustment. In drum brakes, look for lining wear, glazing, cracking, or separation from the shoe. In disc brakes, inspect pad thickness, uneven wear patterns, and signs of overheating such as discoloration or crumbling edges.
Operational symptoms also matter: longer stopping distances, slipping while holding a load, increased required stroke to release/apply, abnormal noise (squeal, chatter), or excessive dust can indicate material degradation or misalignment. If linings are contaminated with oil or hydraulic fluid, replacement is typically required—cleaning rarely restores original friction reliably.
Always replace as a set on both sides to maintain balanced torque. After replacement, verify air gap/clearance, check spring force (where applicable), and perform a controlled functional test. Using OEM-spec friction materials helps preserve designed friction coefficient and heat performance.
