Pre-purchase brake tests – tips from Bendix

For many motorists, increasing cost of living pressures means that a trip to the new car showroom to upgrade the family hauler or work vehicle may be out of reach.

The good news is that the used car market can offer an attractive alternative for people in the market for a ‘new’ car, especially now that used prices are retreating following their high values during COVID.

There are a few options available to source a replacement vehicle, namely purchasing from a private seller, through a dealership or via an auction house. Most late model vehicles will likely be sold with a certificate of roadworthiness and car dealers in Australia will also need to provide a warranty, normally spanning three months or 5,000km. In New Zealand, protection is available under the Consumer Guarantees Act.

Whatever the origin of the vehicle, prospective owners should still perform their own due diligence to ensure the mechanical condition of the vehicle meets their expectations once they get it back home.

Where braking is concerned, there are some simple tests that can be performed to determine the overall health of the braking system – a good place to begin is with a visual inspection. To do this, removing the wheels is best, as this will provide clear access to the brake rotors, pads and brake hoses.

When conducting visual checks of the braking system, it's preferable to remove the wheels to provide clear access to rotors, pads and brake hoses.

Pads should be inspected for thickness, this can be done by checking how much friction material remains – there’s no need to remove the pads. A new brake pad will generally be around 10mm thick; most brake specialists recommend replacing the brake pads when thickness sits at around 3mm.

Next up are the rotors. These should be checked for cracking. By running the fingers over the surface, you’ll also be able to feel the uneven wear or grooves that will negatively affect braking performance. Wear grooves can be a sign of incorrect pad installation; it will mean that the rotor needs to be machined to restore a smooth, flat surface and with it, safe braking.

With the wheels off, there’ll also be good access to the brake hoses. Sight these and feel the hoses for cracks, deformities, connector corrosion or brake fluid leaks. Also inspect the rotor hubs; if they’re showing signs of corrosion, it could be a sign that the vehicle has had a hard life or been poorly maintained.

Check pads for thickness, make sure rotors are free of cracks and don't have wear grooves. Also check for kinks or leaks in the brake hoses.

Once behind the wheel, it’s also important to thoroughly trial the brakes as part of any pre-purchase test drive.

When the brake pedal is applied, it should not sink to the floor or feel spongy. There should also be minimal brake pedal feedback and no vibration or excessive noise when the brakes are pressed.

Pulsing feedback through the brake pedal may indicate warped rotors. A cause of this can be excessive heat which can result in glazing; this is where pad friction material rubs off on the rotor at extreme temperatures.

Warping can also occur due to fast changes in temperatures; think of a

heavily loaded four-wheel drive that’s just completed a long steep decent and is straight into a water crossing. Other symptoms of warping could include jittery or inconsistent braking, vibration during braking; or more subtle indicators including excessive squealing when braking or a burning smell.

On the road test, make sure the brakes don't feel spongy and ensure there are no vibrations, noises or excessive pedal feedback when brakes are applied.

Make sure to also test the park brake. This can be done by driving to a safe, inclined area and applying the handbrake. Once engaged, put the vehicle in neutral and carefully take the foot off the primary brake. If the park brake doesn’t securely hold the vehicle, it may require adjustment or there could be a more serious problem.

If prospective owners are not confident to undertake their own inspections, they should engage a trusted mechanic or pre-purchase inspection specialist to test the vehicle on their behalf. And if there is an issue, Bendix offer a full suite of braking components to suit a wide variety of makes and models, offering a high-quality alternative to OEM parts.

If not confident in doing checks, engage a trusted mechanic to undertake the pre-purchase inspection.