Any issue with your car's braking system is likely to be worrying. Brake chatter is a common symptom experienced by many car owners, and it's relatively easy to recognize. If you step on your brakes and feel a noticeable vibration or shuddering, you're likely experiencing brake chatter. It's typical to feel chatter more through your steering wheel than through the car's chassis.

Brake chatter can often start relatively subtle and worsen over time, eventually making it hard to control your vehicle if you need to make a hard stop. The good news is that brake chatter or shudder isn't usually an immediately dangerous issue, but it is one you'll need to address as soon as possible. In most cases, the shaking is attributable to one of these three common causes.

1. Excessively Worn Rotors

The "business end" of a disc braking system consists of the rotors (or discs) and brake pads. While recommendations vary between manufacturers, you typically don't need to replace your brake rotors with every braking service. Instead, replacing the brake pads and leaving the rotors in place for a few brake jobs is more common.

However, the rotors will eventually wear down, and ignoring the signs of wear can reduce braking performance. The rotor material may become too thin, or the surface can develop glazed hot spots, leading to uneven braking and noticeable chatter. Quickly replacing the affected rotors can usually resolve the issue without causing further damage to your braking system.

2. Stuck Calipers

The calipers use hydraulic pressure to compress your brake pads against your rotors and create the friction necessary to stop your car. Unfortunately, numerous problems can cause the pistons in the calipers to become stuck. In most cases, a stuck caliper will leave the brake pad in constant contact with the rotors, creating numerous issues.

Constant contact between the rotor and pads will generate excessive heat, rapidly wear out the brake pads, and create large amounts of brake dust. You'll often notice vibrations and chatter as the problem worsens since the heat and dust will create uneven wear on the rotors. If you notice any of these symptoms, it's important to have a brake technician check your car as soon as possible.

3. Improper Lug Nut Torque

Can the lug nuts on your wheels affect your brakes? Maybe! Your lug nuts hold your wheels onto your car, but they also push against your brake rotors. In fact, if you look at a typical brake rotor, you'll notice several holes where your lug nuts or bolts pass through. Tightening your lug nuts down too much or using inconsistent torque can cause subtle deformations in the rotor.

Correcting the torque on your lug nuts may resolve the issue, but you should still have a qualified brake technician perform an inspection. Overtightened lug nuts can potentially permanently warp your rotors, leading to uneven brake wear and unpleasant chattering and vibrations. A brake shop can check for rotor warping and perform a replacement if necessary. 

For more info about brake repair, contact a local shop.