When it comes to car maintenance, there are some tasks that are better left for somebody else to tackle. An oil change, for example, doesn’t cost much more to have done at a shop than if you were to buy a new filter and five quarts of synthetic. No thanks. I’ll let a mechanic get their hands dirty.
There was a time that wasn’t the case for me. Both of my parents retired from General Motors and I spent many years wrenching on cars and motorcycles. Our vehicles never got worked on by a mechanic. But these days, I pick and choose which jobs I want to handle myself.
Brakes are one such job. Everybody who owns a car or truck should learn how to replace their brake pads and rotors. The markup at a service center—especially a car dealership—can be exorbitant. But, a brake job can be accomplished quickly and easily, with just a handful of cheap tools, for less than half the cost.
Recently, a colleague here at Popular Mechanics mentioned that he had an appointment the next day to get the front brakes replaced on his 2016 Mazda 3. The cost he was quoted: $477.
That’s absurd. Though, I’m sure I responded with some kind of expletive. I told him to go buy rotors and pads at the local auto parts store for a fraction of that cost and I would install them for him on our lunch break. In the process, he learned just how easy the job is. Bonus: We get to share that process with you, too.
So, read on, and be prepared to save yourself a couple hundred bucks the next time the garage says you need new stoppers.
A word of advice: If you’re doing this, be sure you have all the parts and necessary tools before you start taking your car apart. Or, make sure you have a reliable ride to get back to the auto parts store. Trust me on this one.
Now, let’s get those brakes back in working order.
Tools You’ll Need
Remove the Wheel
Before you bust out the car jack, take that lug nut wrench from your car’s trunk and break the lug nuts free. Don’t completely remove them, just crack them loose while the weight of the car is still on the wheel. Then jack up the car and put a jack stand underneath for safety—never trust that little scissor jack if you have to work under a car. (Also, always chock the opposite tire; If you’re working on the front/driver’s brakes, wedge a brick or wood against the rear/passenger tire so the car can’t move and fall off the jack or stand.)
Once the wheel is off, turn the steering wheel all the way to the direction that you’re working. This will give you easier access to all the bolts you need to remove.
Care for Your Calipers
Unbolt the caliper first. There are likely two bolts on the inner side to be removed. Since we are demonstrating this on a Mazda 3, here’s a good diagram to reference. The caliper bolts are labeled number 4, the caliper is number 5. You may need to use an open box wrench or Vise-Grip pliers to hold the slide pin, so you can loosen the bolt.
Do not disconnect the caliper from the brake line, but also be careful that you don’t damage that line. I like to hang the caliper up on the spring of the front shock so it’s out of the way. You can do this with a zip tie or small length of wire. I have some S-shaped hooks from Ikea, originally meant for hanging pots and pans on a kitchen rack, that I use in my garage for all manner of things. One works perfectly to suspend the caliper safely out of the way.
Remove the Pad Mounting Support
Next, loosen the two larger bolts that hold the mounting bracket for the pads. You’ll almost certainly need a breaker bar or a long-handled ratchet like shown above to get these two bolts loose. Those extra 6 inches on the handle make a huge difference compared to a standard ratchet. But, if you don’t have one, you can slip a length of pipe over the handle of your ratchet to make it longer and give yourself some extra leverage.
Bash the Rotor Free
The rotor, too, is going to be difficult to remove. The rust buildup where it meets the hub makes it stick like glue. To break it free, grab a hefty hammer and a small chunk of wood and go to town. I used a big ball peen hammer because we were putting on brand new rotors and I wasn’t worried about damaging the old rotors. When you give it a few good whacks from the back or front, you’ll see rust start to rain down. You know you’re getting close.
Use a wire brush to wipe away any rust from the hub, then install the new rotor. Blast the new rotor with brake cleaner before installing it and be sure not to touch the stopping surfaces with your oily hands, then position it over the hub bolts and press it into place.
Swap and Silence the Pads
Remove the old pads and pay attention to the orientation of any guide plates and the wear indicator. The pads are held in with springs and shouldn’t be too difficult to remove, but you can tap the ends with a screw driver if you need to persuade it to let loose.
As you place the new pads into the support bracket, try to not touch the face of the pads. I like to wear latex gloves during this step. It can be a little tricky to get the pads seated, especially if you’re just touching the edges of the brake pads. Be sure to push the ends deep into the clips so the pad fits. Then wiggle them apart so you have a nice wide gap for the rotor in the next step.
Put the pads and bracket back over the rotor and reinsert the bolts. Use some Thread Locker (blue or red) to keep the bolts from vibrating loose. Then apply disc quiet paste to the backside of the pads. This will help reduce noise later. Be sure to not get any of it on the stopping face of the pads or on the rotor. You want to keep these surfaces clean so they do, in fact, stop your car!
Retract the Caliper Piston
Since you have new, thicker brake pads, they won’t fit within the caliper until you compress the piston. (As the brake pads wear down, the piston extends further to ensure you have enough stopping power every time you hit the brake pedal.) To do this, you can use a special tool as shown here. Or you can use a simple C clamp. In any case, always use your old brake pad over top of the piston as you press it back in to ensure you don’t damage the piston. It doesn’t take much force, but just slowly back it out.
Note: This process works fine for front brakes. But, if you’re changing the rear brakes, you may need another special tool to compress the caliper because of the emergency brake. We detailed that in another article. While some cars will require the special tool, others, like Mazdas with the electronic emergency brake, require a convoluted sequence of actions involving the ignition button, gas pedal, and brake switch. It’s nowhere near as memorable as up-up-down-down-left-right-left-right-B-A, so I have to Google mine every time I work on my brakes. Search to see if your car uses a tool or magic button press combination.
Reinstall the Caliper
Now you have enough clearance in the caliper to get it over the new brake pads and rotor. To make it fit easily, squeeze the brake pads against the rotor with your hand, so that they’re as close together as possible. Then position the caliper and reinsert the bolts. Again, you may need to use a second wrench or pliers to keep the pin from spinning, or you might just be able to hold them in place with your fingers.
Not shown here, but you should also pick up a brake dust boot kit and replace the bushings and rubber boot to keep the guide pins clean and free of debris.
Put the Wheel Back On
With the wheel in place, hand tighten the lug nuts and ensure the wheel is firmly seated against the hub, then use your socket wrench to just lightly snug them up before lowering the car back onto the ground. Then, with the weight of the car on the tire, tighten the lug nuts using a star or criss-cross pattern. It’s recommended to refer to your owner’s manual to see if there’s a torque specification.
Pump the Brakes
With everything all put back in place, it’s time to start up your car. But, don’t put the car in Drive just yet. The first time you pump the brakes, you’ll find the pedal is soft. Remember how we compressed that piston in the calipers earlier? It won’t fully squeeze the brake pads until you’ve stepped on the brake pedal a couple times. You’ll start to feel the normal pressure return.
Then hit the road. Some folks recommend bedding the brakes—a series of accelerations and quick slow downs. If you have easy access to empty roads, go for it. But, going from 55 mph to 5 mph on busy streets is a good way to get yourself rear-ended. Then, hit the open road, knowing you earned a few “free” tanks of gas by doing the brakes yourself.
Jeff is Runner-in-Chief for Runner’s World, guiding the brand’s shoes and gear coverage. A true shoe dog, he’s spent more than a decade testing and reviewing shoes. In 2017, he ran in 285 different pairs of shoes, including a streak of 257 days wearing a different model.
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