Question 1

When a brake caliper needs replacing

Accepted Answer

A brake caliper presses the brake pads against the brake disc and generates braking force. Inside the caliper are a piston and seals that wear over time. Finnish road salt also corrodes the caliper slide pins, so the pads can't move freely and the caliper gets "stuck".

Symptoms of a seized caliper: pulling to one side on braking, uneven pad wear (one pad fully worn, the other barely), a strong burning smell after braking and brake disc overheating. At worst the brake stays partly applied continuously, heating the wheel well and raising fuel consumption.

Question 2

How a brake caliper is replaced

Accepted Answer

The wheel is removed and the brake hose is clamped shut so fluid doesn't escape. The old caliper is undone from its mounts and removed. A new (or remanufactured) caliper is fitted in place, the brake hose is reconnected and new pads are installed.

The brake system is bled carefully — old fluid is pushed out with a pressure bleeder until only new fluid with no bubbles remains. The test drive checks for even braking and no sideways pull.

Question 3

Why do brake calipers seize?

Accepted Answer

Caliper seizure most commonly results from slide pin and boot deterioration. Finnish road salt reaches the metal surface via these and corrodes it. Brake fluid neglect can also cause problems — moist fluid corrodes the caliper piston and it seizes. Regular brake service, where the caliper is cleaned and relubricated with fresh high-temperature grease, significantly extends caliper life.

Brake Caliper Replacement in Vantaa