Doing your own brake work, if done correctly, can save you a lot of money. But if a brake job is done incorrectly, it could cost more than if you were paid a professional to do the job to begin with. I have done hundreds of brake jobs in the last 25 years as a Master Auto Technician and in this article I will describe some of the basics. I also point out some common mistakes that beginners and even professionals can make when doing brake work.
Pulsating?
If the car shakes when the brakes are applied, this means that the brake rotors are deformed. Excessive side-to-side runout causes the car to jerk, especially when stopping quickly at highway speeds. Rotors can be machined or repaired to work again as long as they are thick enough. If there is no brake pulsation or jolt, the brake pads can be replaced without machining. However, in my experience, if the rotors are not machined or replaced when doing brake work, most of the time there will be excessive squeaking noises after a very short time. I recommend taking care of machined or replaced rotors when doing brake work.
Raise the car safely
Sounds a bit too basic doesn’t it? I have seen many people under cars without having a jack stand in place for safety. Hydraulic jacks are great, but what if one slips or fails in some way while someone is working under the car? I can’t stress enough the importance of having the car safely lifted with a jack stand in place, in case the car falls over for some reason. An under car jack stand is very important any time work needs to be done under the car, such as for oil changes, starter replacement, or any other job that could crush a person if the jack fails. I once worked with a mechanic who was changing his starter at home. His hydraulic jack had a slow leak and before he realized the car was gradually coming down towards him, he was trapped under the car and was unable to get out from underneath. The compression of his chest only allowed him to breathe very little, limiting his ability to call for help. Luckily, a friend passed by, saw what was happening and got his car in. If it weren’t for luck this could have had a totally different outcome, your mistake could have cost you your life.
Wheel, Caliper and Rotor Removal
After removing the wheels, find the caliper bolts and check what type of head the bolts have to determine what tools will be needed. Common fasteners will have regular, allen, or torx bolt heads. Typically there will be two bolts holding the caliper and two bolts holding the caliper bracket. Usually the caliper can only be removed if only the brake pads are replaced. Suspend the caliper with a bungee cord or something similar to prevent the weight of the caliper from possibly damaging the brake hose. If the rotor is to be removed for machining or replacement most of the time, the caliper bracket will also need to be removed. The rotors will simply slide out or in old style setups they will be supported by the wheel bearings. The majority today’s cars will have rotors that will slide. Wheel bearings of this design cannot be repaired, which means they are greased for life and can only be replaced when they fail so that they are not repackaged with grease during brake work like in the past.
Pushing the piston
It is necessary to push the brake caliper piston in to install the new brake pads. The piston slowly extends as the brake pads wear out. This is the reason why no brake adjustment is needed for the disc brake system, it is basically self adjusting. Large channel locking pliers can be used to compress the piston back into the caliper. There are also brake tools that can be used to push the piston in. A large C-clamp used to be my favorite method of returning the piston to the caliper. If you work with rear disc brakes, a piston recoil tool such as the KD 41540 (one from Den) It is recommended to open the brake bleeder screw when pushing the piston, this allows it to re-enter more easily and prevents possible damage to the cylinder master and / or pump or ABS (anti-lock brake) valves that force old fluid back into the system … Closing the bleed valve immediately after pushing in the caliper piston will ensure that it is not necessary to bleed the brakes. caliper are broken, the caliper needs to be replaced. Broken boots will allow moisture and dirt to enter the surrounding area of the piston and cause it to stick or stick. There are slides on some caliper holders that can freeze or sixteen too which can cause uneven pad wear. The sliders must be disassembled and lubricated with silicone gel or disc brake grease. The slides must run freely. e for the brakes to work properly.
Installing the brake pads and calipers
Take note of the possible differences between the brake pads on the left side and the brake pads on the right side. Also, sometimes there are differences in the internal and external brake pads. Obviously, the friction part of the brake pad goes towards the rotor. My uncle long ago, before I started working on cars, did brake work on his Cadillac. I remember hearing you put the brake pads backwards! Ruined your brake rotors. It seems like an impossible mistake, but when you are not familiar with what you are doing, anything is possible. With aftermarket brake pads, most of the time they will come with their own noise isolators that fit the back of the pads. Some will have sticky backs that will have plastic to peel off before installing, others may have built-in tabs. Note that if supplied, the OE (original equipment) pad insulators will not be reused. Once the pads are in place, be careful not to TWIST the brake caliper hoses when replacing the calipers. Twisting them is a common mistake and hoses can kink when cornering.
Pump the brake pedal!
Once everything is back together, it’s time for a test drive. But first step on the brake pedal before starting the car! The pedal will go to the floor and if it doesn’t, you may be heading for a crash. When the pedal is pumped, the pistons are pushed out and the pedal becomes firm. There was an auto technician I was working with who forgot to pump the brakes after doing brake work. He walked out of his service area, when he hit the brakes the car kept going and got into the car that was halfway on the rack behind him. The rear window of the car he was driving broke, luckily there was no other damage.
There are many types of brake systems, but most disc brakes are basically the same. Following the steps that I have listed here should help you replace the brake pads. But if you’re not completely sure, it’s always a good idea to ask a friend with hands-on experience to guide you on your first brake job.