Brake Caliper Guide Pin Kit

The brake caliper guide pins are two round metal pins on each brake caliper where the brake piston assembly sits. They're called guide pins because they're responsible for guiding the proper angle for how the brake pad meets the disc.

If the caliper is not free to move, the culprit might be bent or binding guide pins. Even if guide pins are not damaged, swollen or hardened guide seals or lack of lubrication may cause the caliper to bind resulting in uneven pad wear.

Always inspect all mounting surfaces and hardware for corrosion, wear or misalignment.

Most sliding calipers use a rubber or plastic insulator around the mounting bolts of the caliper. This sleeve of soft material loses resiliency over its lifetime. This is hastened by the high-temperature environment of the brakes.

As materials wear, instead of being round the pins are flattened by the torque from the brakes into an oval shape that can cause excessive caliper movement, which in turn, can cause noise like rattles and thumps even if the brakes are not applied. These rattles often stop when the brakes are applied.

Always inspect and replace if necessary any dust boots or guide pin inner sleeves that protect the caliper guide pins. If the soft parts look ok, clean out all the old lubricant and replace with new silicone grease.

Unlike steel, soft parts like rubber are sensitive to chemicals. Choosing the right lubricant for these parts is critical to ensuring the integrity of the part, we strongly recommend using only silicone grease, other lubricants will cause the rubber dust boots to swell and degrade. If the caliper boots fail to make a seal with the caliper carrier and bolt, water can be sucked into the cavity as the bracket contracts and cools.

Cars keep evolving, and as they evolve there are new procedures and problems that go along with that evolution. Not the least of which are modern brakes, now here we have a four-piston caliper, they've been around for years, but they typically were not used on garden-variety cars and sometimes they are today.

Now the big thing with a four piston caliper is that it's mounted rigidly, it doesn't move, it has the four pistons the four pistons have to work in unison which means that periodically you have to clean around the pistons because dirt can actually migrate through the seals and cause the pistons bind. The other thing is if the pistons or the caliper doesn't move and the pistons do, that means that the pads move on the pins. So those pins have to be lubricated in order for the pads to move smoothly, and if they don't if one of these pistons is out of sync or if you don't move the pad properly you can wind up with what we have here. One end is like new the other end is almost worn out. So, periodic cleaning and lubrication, very good idea.

Now over here we have a two piston caliper, now the pistons are side by side and the caliper slides back and forth, now the thing with that is because it slides, these slide pins right here have to be lubricated in order to keep the caliper moving smoothly and not rocking on its slides. Again, you want to clean around the pistons and so on during a normal brake inspection.

And finally we have our old tried and true single piston caliper that again slides back and forth on some type of mechanism. It, like all the others, needs to be lubricated so that it slides freely. If you have uneven wear on a pad or something like that, suspect that there's probably an issue with the caliper or the sliding mechanism of the caliper. Now the thing here is that you should be checking your brakes and lubricating all this stuff about every 12-15 thousand miles or once a year. But, the product you use has to be designed specifically for brakes because of the excessive heat, you can't use normal grease because normal grease will melt and go away. It also collects dirt and the dirt makes things bind up. So proper maintenance, pads will last longer, brakes will work better.