Brake caliper slide pin

Brake caliper slide pin — replace, unseize, reuse

The brake caliper slide pin is one of the weak links on a floating brake caliper. If the caliper can’t slide easily on the caliper slide pin, the brake pads can’t release from the rotor. The result? Premature brake pad wear, uneven brake pad wear, and even braking failure due to overheated brake fluid.

Brake caliper slide pin corrosion is the biggest problem

The brake caliper slide pins are protected against moisture intrusion by rubber boots. New boots should be installed every time you renew your brake pads. They’re cheap, easy to install, and your best protection against seized caliper slide pins and corrosion.

Start by checking for torn caliper slide pin boots

If the caliper slide pin boots are missing, torn or aged, chances are water has entered the bore and caused rust to form.

Do not re-use these components. Purchase new caliper slide pins and a new boot set.

If the caliper slide pins are built into the bracket

You have two choices; purchase a rebuilt bracket or buy a complete rebuilt caliper with a new bracket.

Best way to unseize a brake caliper slide pin

Cut off the rubber boot. Soak the caliper slide pin with rust penetrant like PB Blaster. Allow to soak. If the pin bores are in the caliper, vibrate the caliper by tapping with a hammer. If the pin bores are in the bracket, vibrate the bracket by tapping with a hammer. The vibration helps break up the rust and allows the rust penetrant to wick into the cracks.

Then try rotating the slide pins or applying force to separate the caliper from the bracket. This will take some time and patience. DO NOT USE heat. You’ll damage the caliper piston, piston seal, and dust boot. If you’re at the point where you’re contemplating using a torch, you may as well stop trying to save the old caliper and just purchase a rebuilt caliper, because the heat from your torch will damage it any way.

Do not try to save the old rusted caliper slide pins

If they’re rusted, the protective coating has been compromised and they’ll just rust again

Lubricate the new slide pins with the silicone grease

Anti-seize is NOT the correct grease for caliper slide pins. You need a high-temperature synthetic silicone grease for caliper slide pins. Anti-seize isn’t rated for high temperatures and isn’t compatible with rubber parts.

©. 2021 Rick Muscoplat