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Brakes

Brakes explained: pads, discs, fluid and safety

How the braking system works, what each part does, the warning signs and the right replacement schedule.

Aug 17, 2026 ✔ Free
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How the system works

You press the pedal, the master cylinder pressurizes brake fluid, and that pressure moves the calipers to clamp the pads against the discs. The friction turns motion into heat.

Pads and discs

  • New pads have 10–12 mm of material; replace at 3 mm
  • Discs have a minimum thickness stamped on the hub — measure, do not guess
  • Replace discs in pairs, pads with them
  • Wear indicator squeals when pads are near the limit

Warning signs

  • Squeal: pads near the limit
  • Grind: pads gone — discs at risk
  • Spongy pedal: air or low fluid
  • Pedal sinks: a leak
  • Judder: disc run-out
  • Pulling to one side: stuck caliper or uneven wear

Brake fluid

Brake fluid absorbs moisture over time, which lowers the boiling point and corrodes the system. Flush it every two years. Never mix DOT 3/4 with DOT 5 silicone.

Questions about this article

Pads typically last 30,000–50,000 km and discs longer, but it depends on driving. Inspect at every tire change and flush the fluid every two years.
Pulsing usually means disc run-out (warping). It increases stopping distance and wears pads unevenly — get the discs measured.
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