Brake Job: How to Change Your Brake Pads and Rotors
By Courtney Evans
Do-it-yourself and save money! Save money by doing-it-yourself. No matter how you say it, it can really add up. I like the phrase so much that I think I’ll make it my new mantra. Maybe you should too. I’ve literally saved thousands of dollars by doing my own auto repairs.
In last week’s issue, we discussed the brake job. Actually, we identified the parts or components that make up your vehicle’s brake system. If you missed last weeks issue, please read it here, as I consider it a prerequisite to today’s issue. The purpose of that issue was to familiarize you with those parts and get you nice and comfy so that you can tackle the brake job yourself. This is where the rubber meets the road when it comes to savings and the do-it-yourself brake job is the subject of this week’s essay.
The job is relatively simple when compared to other repairs but there are quite a few steps involved and they should be followed carefully. We’re going to break it down into 3 parts; (1) removing the brake pads, (1a) removing and replacing the rotors (brake discs), and (2) reinstalling the brake pads. If you’re just replacing your brake pads, skip 1a and jump to part 2 after completing part 1.
I should mention that we’re discussing disc brakes only. Disc brakes will either be found on the front wheels only or both front and rear. Some vehicles have drum brakes on the rear wheels and the procedure for replacing them is a little different and will be discussed at a later date. OK, let’s go.
Brake rotors [a.k.a. discs] (if applicable)
Brake rotor hold-down bolts (if applicable)
Caliper guide bolts (replace if bad)
Caliper guide bolt bushings
Brake pad sensor wires(if applicable)
Brake parts cleaner
Brake parts grease
Ratchet & Sockets (SAE and Metric)
Allen bits for ratchet
Various screw drivers
Wire cleaning brush
Caliper piston tool/medium C-clamp
Changing the brake pads
First, decide if your going to replace the pads at all four wheels or just two. You’ll replace the pads in pairs, front wheels or rear wheels. For a complete job and best results, do all 4 wheels. If your budget and/or time constraints won’t allow it, do front or rear. The front wheel brake calipers, pads, and rotors are larger than those on the rear and cost a little more. The procedures for both are basically the same.
By determining whether the brake job is for two wheels or four will also determine whether you’ll jack the front, rear, or both ends of the vehicle. If you have an impact gun to remove the lug nuts from the wheels, you can proceed with the jacking. If you have to remove the lug nuts using a crowbar, you should loosen them just a little (breaking the seize) while the wheels are on the ground. Once the wheels are in the air, they may turn freely, which will make removing the lug nuts very difficult, if not impossible. Safely jack the vehicle and then support it on jack stands. Never perform work while a vehicle is only supported by a jack. Jacks fail and you may be putting your life in danger.
Once a wheel is removed, remove the anti-rattle clip (if applicable) by prying it and sliding it out with a large screwdriver. Next, let’s remove the brake caliper. For the front wheels, it may be necessary to turn the steering completely either to the right or to the left to access the caliper guide bolts. Typically, they are on the back side of the caliper. The caliper guide bolts may have dust caps. These will be made of rubber or plastic. Use a small screwdriver to pry them out. Once the caps are removed, the bolt heads will be exposed.
Using your ratchet and the appropriate socket or Allen bit, remove the 2 bolts. Grasp the caliper and pull it away from the rotor. You may need to use a large screwdriver to pry it loose. Remove the two brake pads from the caliper, prying if necessary. One brake pad may be attached to the caliper piston by a clip. Loosen the clip and the pad will fall out. If your vehicle is equipped with brake pad sensor wires, carefully remove the wire from the pad. The sensor wire will be on one pad of either the right or left wheel. Make note of which wheel has the wire.
Now, its time to recompress the caliper piston. As brake pads wear, they cause the piston to push further and further out of the caliper. The piston must be pushed back in so that you can fit the new, thicker brake pad in place. You can use one of the old pads and a piston compression tool or c-clamp to push it back in. Simply place the old pad on top of the piston and tighten the tool or c-clamp to press it back in place.
Use your bungee cord to hang the heavy caliper from the spring or suspension carrier as you get ready to install the new pads. Never calipers to hang by their brake lines as they are heavy and will damage the line. Place a few rags under the parts and spray brake parts cleaner liberally to the caliper, bolts, bracket, etc. to thoroughly clean everything. You may need to use your wire cleaning brush as well.
Removing the brake rotor (disc)
If you’re replacing your brake rotors as well, follow this procedure. Now that the caliper is removed, its time to remove the brake rotor. First, you need to remove the caliper bracket. This is what the caliper was resting on and is also where you previously unscrewed the caliper guide bolts. The bracket is connected via two bolts. You need to use your breaker bar and the appropriate socket to remove it.
Once the bracket is remove, its time to remove the brake rotor (disc). The rotor is held in place by either one or two hold down bolts. These bolts will be comparatively smaller than the others and may require the use of your Allen wrench. Support the brake rotor as you loosen the bolts. Remove the bolts. If the rotor does not come off, you may need to use a rubber mallet and hammer it from the back to loosen it. Corrosion between the rotor and wheel hub may have caused it to seize.
Reinstalling the brake rotor
You’ll reinstall the rotor in the reverse order. To prevent the rotor from seizing to the wheel hub, apply a thin layer of anti-seize compound to the wheel hub before putting the brake rotor back on. I would also put a little anti-seize compound on the threads of the rotor hold-down bolt. Tighten all bolts using your torque wrench set at the appropriate setting.
Apply a thin layer of anti-seize compound to the threads of the caliper bracket bolts as well. Be careful not to get any on the surface of the rotor. Following these steps will make your next brake rotor change a breeze.
Installing new brake pads
Note: Some anti-squeal compound type require curing for at least six hours before installing the pads on the vehicle. Read the instructions on the product to determine whether you should apply it to the back of the new pads on the night before.
First, apply the anti-squeal compound to the back of the pads, not to the surface that comes in contact with the rotors. Remove the bungee cord and support the caliper. Next, carefully install the pads into the brake caliper. The two pads should differ in appearance and fit so you shouldn’t get confused as to which fits where. If your vehicle is equipped with brake pad sensor wires, carefully install the wire in the pad.
Install the caliper/pad assembly over the top of the brake rotor. Be sure to seat the brake pads into the notches of the caliper bracket. Align the holes in the caliper with the holes in the caliper bracket. Apply a thin layer of brake parts grease to the caliper guide bolts and slide them in. Tighten the bolts using your torque wrench at the appropriate setting. You can find the bolt torque settings in your service manual, owner’s manual, and of course the internet. Your local auto parts store will be helpful as well. Reinstall the caliper guide bolt caps to keep the brake dust out.
Reinstall the anti-rattle clip (if applicable) using your large screwdriver. This will take a little patience and for me, this one step took the most time. Persevere.
Once you’ve completed pad change, you can reinstall each wheel.
Before you move the vehicle, be sure to pump the brakes several times until the pedal feels firm. The next step is to break the brake pads in. This procedure is also called “bedding” the brakes. You can find lots of information about this procedure on the internet. Basically, it involves making a series of stops from 55 mph while applying more brake pedal pressure with each successive stop. Five to ten stops is usually all that is necessary.
Performing your own brake job is not difficult and the savings can be huge! Not to mention the confidence boost you’ll get. I know you can do it. I have confidence in your abilities. Tell those service managers “I’ll handle it”, next time they try to separate you from your cash. I sure did and you will too!