Weekend Herald

Braking the sound barrier

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Most of us can relate to this scenario. You are slowing at an intersecti­on but, instead of coming to a stop quietly, your brakes squeal and scream their way to a halt.

It could be a sign that your brakes require some attention. With so many parts to a braking system, there are a few common issues that can be experience­d during the ownership of a vehicle.

Vehicle braking systems rely on friction generated between two components of different material types in various combinatio­ns of a steel disc/brake pad, or steel drum/brake shoe as a method to slow a vehicle. There is a high possibilit­y for a brake system to make noise.

Brake pad material constructi­on can vary based on the quality and brand of the product used. Pads can have high heat and noise resisting capabiliti­es, and low wear or dust generating capabiliti­es. However, sometimes the better the brake pad, the harder they are on the disc they run against.

IF YOU ARE DRIVING A VEHICLE WITH NOISY BRAKES, GET THEM CHECKED AS SOON AS POSSIBLE. IT COULD BE SOMETHING SIMPLE OR THERE MAY BE SIGNS THAT MORE WORK IS REQUIRED

The downside of replacing pads only

If an old disc just gets new pads, they will need bedding in and there’s a high chance that the brakes may take longer to be as effective as they once were, and noises may also develop.

This is because the new pads have a smooth flat surface, while the old disc may have scores and scratches from the old brake pads.

To prevent this happening, a portable lathe can take a small shaving from each side of the disc, giving it a nice smooth surface like new.

A downside to this is that the disc gets thinner every time a disc is skimmed which can make it easier for a brake disc to warp in the future.

Ultimately if the discs are getting close to their limits, it would be best to put new discs on with a fresh set of pads.

As most of the braking force is carried out by the front disc brakes, the rear brakes (discs or drum) are unlikely to need attention as often. A rear drum brake system incorporat­es the same principles as disc, but the constructi­on and operation methods slightly differ.

Brake fluid is the life blood of the braking system; it is also hydroscopi­c (absorbs moisture from the atmosphere). It provides the link from the brake pedal to the components doing the work at the wheels. Every vehicle has a recommende­d brake fluid replacemen­t schedule that ensures the fluid remains clean, fresh and free from moisture.

When’s the right time to replace?

Brake pads have warning indicators to help inform drivers when they should be replaced. Metal strips are set to a specific distance where they’ll start to rub against the disc when the pads become just a few millimetre­s thick, alerting the driver that the brake material may be low.

The indicator rubbing noise is usually most noticeable when the brakes aren’t applied and it’ll become less obvious when the brakes are used. If you notice this happening, it’s best practice to go to a garage to get the pads replaced.

If you are driving a vehicle with noisy brakes, get them checked as soon as possible. It could be something simple or there may be signs that more work is required. Either way, it’s important to take a closer look to ensure your vehicle stays safe on the road.

 ??  ?? Brake pads can vary based on the quality and brand of the product used.
Brake pads can vary based on the quality and brand of the product used.

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