Old Brake Pads: What Should I Do With It?
What are brake pads and how do they work?
Brake pads are made of specially formulated friction material that presses against the brake disc or rotor in order to stop the wheels from spinning when the brakes are applied. They are typically made of semi-metallic or ceramic compounds that can withstand extremely high temperatures caused by friction.
Inside each brake caliper are a pair of brake pads – one on either side of the rotor. When the brake pedal is pushed, hydraulic pressure forces the brake caliper pistons to clamp the two brake pads against the rotor on both sides. The friction between the pads and the rotor slows the rotor down, which in turn slows the wheels and vehicle.
The brake pads are designed to take the brunt of the friction wear and heat, rather than the more expensive rotor. So over time and repeated braking, the brake pads wear down and get thinner. Eventually they will wear down far enough that they require replacement. The rotors usually last much longer, so only need replacing every few brake pad changes. [1]
[1] How Disc Brakes Work. (n.d.). Auto | HowStuffWorks. https://auto.howstuffworks.com/auto-parts/brakes/brake-types/disc-brake1.htm
When should brake pads be replaced?
Brake pads should typically be replaced every 30,000 to 70,000 miles depending on driving conditions, according to Harr Toyota (https://www.harrtoyota.com/how-often-should-you-replace-brake-pads-and-rotors-worcester-ma/). When the pad material is worn down to 2-3mm, it’s time to replace them. You’ll also want to replace your brake pads if you start to hear screeching or grinding noises when braking, which indicates the pad material is nearly worn away.
Dangers of driving with worn brake pads
Driving with overly worn brake pads is extremely dangerous and can lead to potentially hazardous situations. As brake pads wear down over time, the amount of friction material available to grip the brake rotors is reduced. This leads to significantly longer stopping distances, even with moderate brake pedal pressure (Source). With worn brake pads, you may find yourself needing to depress the brake pedal much farther and harder to get the vehicle to slow down and stop.
Continuing to drive on worn brake pads can also lead to damage of the brake rotors and calipers. As the brake pads wear thin, the caliper piston has to move farther out to apply the pads to the rotor. This can cause the piston to overextend and get stuck, leading to complete brake failure (Source). Furthermore, worn brake pads allow direct contact between the caliper and rotor. This metal-on-metal contact can severely damage the rotor, requiring significantly more expensive brake repairs.
In extreme cases, worn brake pads can cause complete brake failure and lead to collisions or accidents. It is crucial to have brake pads replaced before they are fully worn to avoid dangerous situations and expensive repairs.
Signs your brake pads need replacing
Some of the most common signs that your brake pads need replacing include high pitched squealing or grinding noises when braking, vibrations in the steering wheel or brake pedal when braking, uneven wear of the brake pads, and visible cracks or damage in the brake pads.
As the brake pads wear down over time, they can start to produce a high pitched squealing or grinding noise when you apply the brakes. This is caused by the brake pad material rubbing against the brake rotor once it reaches a very thin level. According to Performance Honda, this high pitched squealing is one of the earliest signs that you need new brake pads.
Vibrations in the steering wheel or brake pedal when braking can also indicate worn out brake pads. As the pads wear unevenly, it can cause the rotors to warp slightly, leading to pulsations and vibrations felt when braking. This uneven wear is another sign to watch out for.
Visually inspecting the brake pads is important to check for uneven wear patterns or visible cracks and damage. If the pads appear very worn or are falling apart, it’s definitely time for replacement.
How to remove old brake pads
To remove old brake pads, you’ll need to follow these key steps:
First, loosen the lug nuts and jack up the wheel so it can spin freely. Refer to your owner’s manual for the proper jack points on your vehicle. Once the wheel is off the ground, remove the lug nuts completely and take the wheel off. This gives you access to the brake caliper and rotor (Edmunds).
Next, locate the caliper slider bolts that hold the caliper in place. Remove those bolts so you can detach the caliper from the rotor. You may need to wiggle it a bit to get it loose. Be careful not to stretch or damage the brake hose during this step. Use a bungee cord or piece of wire to hang the caliper out of the way (Sangsin).
Before the new pads can go in, you need to push the brake piston on the caliper back into its cylinder. Use a C-clamp for this, placing the clamp ends on either side of the piston. Tighten the clamp slowly and evenly until the piston is fully compressed. Take care not to damage the piston.
Finally, you can remove the pad retaining clips, anti-rattle hardware, and any other fasteners holding the old pads in place. The pads should then slide right out, leaving you ready to install the new set.
Proper disposal of old brake pads
Older brake pads produced before the 1990s can contain asbestos fibers. Asbestos was used in brake pads as a binding material and for heat resistance. However, breathing in asbestos fibers can cause serious health issues like mesothelioma and lung cancer. Because of the health risks, you should not dispose of old brake pads containing asbestos in the normal trash.
The preferred method is to recycle old brake pads. Many auto parts stores like AutoZone and O’Reilly Auto Parts have programs where they accept old brake parts for proper recycling and disposal. You can call ahead to find a location near you that participates. This is often a free community service. The auto parts store sends the used brake pads to a certified recycling facility that can safely process and dispose of asbestos material (https://www.oreillyauto.com/shop/services/recycling).
If that is not an option in your area, most municipalities have designated hazardous waste disposal sites that can properly handle asbestos brake pads. Contact your local waste management authority to ask about sites and procedures for hazardous material drop-off (https://www.epa.gov/asbestos/current-best-practices-preventing-asbestos-exposure-among-brake-and-clutch-repair-0). Asbestos brake pads should be sealed in leak-proof containers for transportation and disposal.
Cost to Replace Brake Pads
The cost to replace brake pads can vary depending on the make and model of the vehicle, but typically ranges from $100 to $300 per axle for parts and labor. The parts themselves usually cost between $30 to $150 per axle. The labor costs tend to run between $100 to $200 per axle to have the work done by a mechanic
Luxury and high performance vehicles tend to be on the higher end of the price range due to more advanced braking systems and higher quality parts. Basic brake pad replacements on standard vehicles can be as low as $150 per axle.
Significant cost savings can be achieved by replacing brake pads yourself and avoiding labor charges. However this requires some automotive experience and comfort working on brakes. Many auto parts stores rent tools to assist with brake pad changes as well.
According to Kelley Blue Book, the average brake pad replacement costs around $150 per axle when done by a mechanic.
When to replace rotors with pads
Often times, brake rotors last through several sets of brake pads. However, if the rotors are worn, damaged, or deeply grooved, it’s recommended to replace them when changing the brake pads for optimal braking performance
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As a general rule, rotors should be replaced every 2nd or 3rd brake pad replacement according to experts. This is because over time brake pads transfer material onto the rotors that causes them to wear down. Replacing the rotors ensures you have smooth, even braking surfaces for new pads to press against. Check your owner’s manual for recommended rotor replacement intervals.
Replacing worn out rotors when installing new brake pads improves braking power, reduces noise, and prevents pulsation in the brake pedal. New rotors provide maximum friction for the fresh brake pads to grip. This gives you shorter stopping distances and better control.
Brake Pad Replacement Best Practices
When replacing brake pads, it is important to follow some best practices. This helps ensure the brake pads are installed correctly and safely.
First, lubricate all contact points where the brake caliper meets the brake pads and mounting hardware with high temperature brake lubricant. This helps reduce noise and ensures smooth brake operation. A small tube of brake lubricant can be purchased at any auto parts store.
Always use jack stands when working under a vehicle during brake service. Relying solely on a jack to support the vehicle creates an unsafe condition. Jack stands provide a stable base and added safety redundancy.
After installing the new brake pads, pump the brake pedal several times to pressurize the system and reseat the caliper pistons against the new pad material. The pedal may feel soft at first, but should quickly firm up as the pistons reset.
New brake pads require a proper bed-in period to transfer pad material onto the brake rotors and ensure optimal braking performance. After installation, brake normally but avoid heavy braking for the first 100-200 miles. The pads and rotors will mate during this period.
For more information, see this guide from AutoZone.
FAQs
Here are answers to some frequently asked questions about brake pads:
Are semi-metallic or ceramic pads better?
Both semi-metallic and ceramic brake pads have pros and cons. Semi-metallic pads tend to be less expensive and provide good braking performance, but produce more brake dust and noise. Ceramic pads cost more but produce less dust and noise. They also tend to be easier on rotors. Many experts recommend ceramic for normal driving and semi-metallic for performance driving (Source).
How can I make pads last longer?
You can extend the life of your brake pads by avoiding hard braking when possible, not resting your foot on the brake pedal, checking brake fluid levels regularly, and having your brakes inspected by a mechanic when you get your oil changed (Source).
Is it safe to drive with worn pads briefly?
It’s not recommended to drive with worn brake pads. However, if they still have a few millimeters of pad left, you may be able to drive carefully for a short distance to a repair shop. But worn pads can fail suddenly so this is not advisable (Source).
What tools do I need for a DIY brake job?
To replace brake pads yourself, you’ll need basic hand tools like wrenches, sockets, screwdrivers, brake grease, a brake pad spreader, a C-clamp, brake cleaner, sandpaper, and a torque wrench. Ensure you have the proper tools for your vehicle’s caliper brackets. You’ll also need a jack and jack stands (Source).