Service Tips for Brake Rotors you Need to Know

Brakes are the largest volume repair in many repair shops today. Depending on your driving style, a proper brake repair can last anywhere from 40,000-60000 miles or more, except for mail delivery vehicles and taxi cabs. Brake pads and rotors offer the foundation of the stability, ABS or traction control system. These complex systems cannot operate properly without a rotor surface and the right friction surface. That’s why extra attention must be paid when performing brake repairs, especially on any late models.

But one question remains: must you replace your rotors each time you change the brake pads? This issue will pop in your mind each time you have to replace your pads. Your braking system is crucial when it comes to safety, and you must consider all aspects of replacing parts carefully. In this post, we will examine the pros and cons of replacing brake rotors and pads at the same time including other service tips.

Although most manufacturers recommend that you replace your rotors when changing the brake pads, this isn’t always necessary. While brake pads and rotors function together, they are different components and wear down independently. Therefore, you must use your discretion (or that of your mechanic) to inspect each part carefully before deciding to replace both of them or not.

Rotors have a certain recommended thickness that you should maintain to be safe. First, you must check on your rotor's thickness and what the manufacturer recommends. In most cases, the measurement is normally stamped on the rotor itself. In case you find out that the thickness is below what’s recommended, you have to replace the rotor immediately.

What if you find out that the rotor borderline is very close to the minimum thickness? Should you still replace it or ignore? Well, the best option is to replace the rotor. It’s very inconveniencing to replace pads and then six months later, you are replacing the rotor. Not to mention that the braking efficiency may reduce during this period because the rotor is getting worn.

There are other considerations you have to take into account while doing the maintenance. Even if you don't replace the components, consider replacing the surface especially if the components appear uneven or damaged. Maybe when braking, your rotor vibrates roughly rather than providing that smooth experience. You can opt to have the surface of the rotor turned or machined at a vehicle repair center.

Several things need to be observed too before you decide to reuse your existing rotor. Is it worth being resurfaced? Are the cooling fins rusty? Fins hold the rotor’s inside to the surface. You have to discard the rotor when you find that the cooling fins are thinning or extreme rust has been building up. For vented and non-vented rotors, be sure to check if they have overheated because this can cause large or small cracks. Cracks can cause a lateral run out, which will deem your rotor unusable. The manufacturer provides specifications for maximum lateral run-out, disc diameter, allowable scoring, parallelism, etc.

Similar conditions apply when installing a new Brake pads and rotors on your vehicle, for instance, hub-to-rotor matching. When rotors are made, they are not trued to the vehicle’s hub but a lathe. Additionally, the shipping and storage of rotors can affect their lateral run out.

In other cases, removing the wheels may disturb the rust between the hub and rotor. So, before the rotors are matched, whether they are being replaced or reused, cleaning has to be done on the rotor and hub surfaces. This will prevent rust and corrosion from building up on the surface between the rotor and hub. Removing the wheel also loosens corrosion, and it constantly changes the contact areas. Ensure that the corrosion from the wheel is cleaned to prevent wheel-offs.

Most wheel-offs relate to corrosion on the wheels, hub and rotor surfaces, especially with aluminum wheels. In case installation is done before thorough cleaning is done, it will cause damage. Clean surfaces also facilitate proper heat transfer from brake components hence promoting proper cooling. A stainless steel wire brush can make a big difference.

All in all, you have to adhere to these basics for your safety. For optimal performance (if you can afford it) consider replacing the brake pads and rotorat the same time. In case your budget is tight, and the rotor is above the recommended minimum level, you can still reuse the rotor. As long as the minimum level is still due, your vehicle is perfectly safe.