How To Change Disc Brakes. A general guide to changing disc brakes on your car.
The brakes on your car need to be replaced. Maybe you’re a beginning Do-It-Yourself type and you’re wondering if this is the kind of auto repair project you could do. Or maybe the cost to have a mechanic do the job is a bit more than your wallet can handle right now, but you’re afraid to have uncle Jim’s buddy do it in trade for a 12 pack of beer. Never fear, installing disc brakes on a car is about as simple as any auto repair project can be.
You’re in luck! The car you are working on has disc brakes to begin with. If your car were an older model, you would have had to contend with the old style drum brakes. These were a nightmare. After beating off the huge hub, you then had a spaghetti mess of tensioned springs and cables to both dismantle then reassemble. But, disc brakes are another story. They are much simpler in design with far less moving parts. In fact, there are very few parts at all. This is a project that even a novice home mechanic can do fairly easily.
Disc brakes will vary in specific design depending on the make and model of the car they were made for. With this in mind, the specific installation steps will vary depending on your car. Since there isn’t room here for a brake repair manual for all makes and models of cars with disc brakes, we will instead touch on the basic steps involved in the replacement of disc brakes on your car. Specific instructions for your car may be included in the box your new brakes come in. If not, consider purchasing a Chilton’s manual. These are catalogue-sized books that provide detailed instructions about every component of your car.
Get The Car Ready to do the brake job by first parking on a flat level surface. Next, make sure the car is in Park and that the Emergency Brake is NOT engaged. If the car has a manual transmission, place the car in gear and block the tires at the opposite end you are working on. The object here is to ensure the car is not going to roll while your working on it.
Jacking the car up is the next step. First, make sure you are using the correct jack for this kind of job. Do Not use the jack that came with your car! These jacks are meant only for tire changing and are not heavy enough or stable enough to support the car safely while doing a brake job. For this task, you will need a floor jack. These are large jacks, normally on rollers, that operate on hydraulics to lift the car. Place the jack under a solid structure such as the car frame. Never place the jack under floor panels or suspension joints. Jack the car up until the jack has reached a point that it is beginning to lift the car. Loosen the lug nuts on the tire, and then continue jacking the car up until the tire lifts off of the ground. Place jack stands under the car to safely support the weight. Remove the lug nuts and then the tire.
The Brake Caliper is now visible along with the rotor. The rotor is the large spinning “wheel” and the caliper is the mechanism that surrounds a section of the rotor. First, inspect the rotor and ensure it is smooth on both sides. If it has grooves, especially deep ones, the rotor may need to be “turned” or machined back smooth. Installing new brakes with a scored rotor will cause the brake pads to wear out much quicker than normal. If the rotor is acceptable, the next step will be removing the caliper.
Removing The Caliper is required because this is where the actual brake pads you are replacing are located. The specific steps and tools for this job will vary depending on your car. But, basically, you will need to remove a retaining bolt from the top and bottom of the caliper. The actual bolt head will likely be facing the engine compartment. Be ready for some strong arming of the bolts as they are often difficult to break loose. With the bolts removed, the caliper should come out easily with a little wiggling or a light tap with a hammer. Remove the caliper from the rotor. DO NOT remove any of the hoses. Inspect the caliper for excessive wear. Also look at the rubber boot around the plunger that’s behind the brake pad. Make sure it isn’t torn or pulled away at one end.
Remove The Old Brake Pads from the caliper. All pads have different retaining mechanisms such as pins, springs or clips. Remove the retainer and pad from the outer side of the caliper but leave the inner pad (the one closest to the large side of the caliper). Next, you need to push the caliper plunger, the cylindrical protrusion behind the old pad, back to a flush position. Using a large C-clamp, place it around the caliper so that one side rests on the remaining old brake pad. Tighten the C-clamp, forcing the plunger in, until the plunger is flush with the caliper body or when it stops moving. Now remove the C-clamp and the remaining brake pad.
Install The New Brake Pads into the caliper. Again, the exact way these will attach will vary depending on the car. Pads should be oriented so that the gray graphite pad faces inward and the curve of the pad matches the curve of the rotor. However they attach to the caliper, they should fit tightly and not move around.
Replacing The Caliper is the next step. With the new pads installed, place the caliper over the rotor and into position so that the caliper boltholes meet up as they did when you removed it. With the caliper lined up, replace the bolts and tighten. With the caliper securely in place, you can now replace the tire and take down the jack. That’s one side, now on to the other!
The Last Step in replacing your disc brakes is to adjust them. Do Not attempt to drive your car until you have completed this step as your brakes will not work properly, if at all. Because you depressed the caliper plunger flush when you installed the brake pads, the caliper needs to adjust so that the plunger is in the proper position. Before you start, check your break fluid and if it is low, fill it to the full line. Next, with you car in park or out of gear if it’s a manual, start it. Now, with slow even pressure, depress your brake pedal. You will notice it probably goes all they way to the floor. Don’t panic, that’s normal. Let off of the pedal and continue pumping the breaks with slow steady strokes. After about 4 to 8 pumps, you should have good brakes. Now, put the car in gear and move it slowly and then brake to ensure you indeed have good brakes.
You have just completed a break job on your car and probably saved yourself a wad of cash in the process.
About Ron Warner
I have never been satisfied with things as they are. Yes I suffer from the "Grass is Greener Syndrome". I have been a ditch digger and the GM of a mid-sized mortgage company. I have worked as a fry cook and the Branch Manager for a major Stock Brokerage firm. A roofer, a car salesman, an IT Network Admin, a landscaper, a radio DJ and the list goes on. 30 years of exposure to such a variety of professions and vocations has given me a wealth of knowledge and a unique insight of the world around us. My family and I have enjoyed the savings I have experienced by being able to do many things for myself rather than needing to hire someone else to do the job. As a consumer, I am much more aware than the average consumer of the tricks, games and ploys used by companies to try and dig more from my wallet. True, some may refer to me as a job hopper. But how many computer geeks can roof their house? What does a car salesman know about investing? Know any Stock Brokers who can change a water heater? Yeah, I did not think so. Yes, Life has been good so far.