In this article we will look at the functions of brake pads, how to determine their wear and replace them brake pads with your own hands.
Brake pad - what is it and what functions does it perform?
The brake pad is an element of the brake system, which is part of any car, as well as the main working “organ”. It is the pad that is responsible for creating acceleration, which slows down the movement of the vehicle due to contact with the surface of the wheel and disc. Thus, the pressing force is “transformed” into braking torque.
Brake systems of the shoe type operate by converting energy. The kinetic energy of the car’s movement is “converted” into heat due to the intense friction of the pad against the disc, wheelset or drum. When you press the corresponding pedal, air pressure, brake fluid, and cable tension are generated in the brake drive. The latter is transmitted to actuators such as cylinders and cam. They are responsible for ensuring that the pad interacts as strongly as possible with the surface of the disc or drum.
The harder it is pressed, the more effective the braking will be. During such interaction, the friction pair, that is, the pad and the disc, become very hot and “absorb” the kinetic energy of the moving vehicle. As a result, it stops.
The brake pad design cannot be called complicated. It is a plate made of metal. It plays the role of a base on which a friction lining is installed. This design “repeats” the shape of the surface with which it interacts (disc, drum), and therefore has the shape of a semicircle or straight.
The pad is fixed to the block using special rivets and glue. On some models of modern cars, the pad is equipped with wear sensors. Modern pads include a specialized friction coating that is designed to protect and maintain structural integrity in extreme conditions (the temperature of the pads during operation of the braking system often reaches 1000 degrees).
Thanks to the presence of a friction coating, the pads are able to withstand operation at extreme temperatures for a long service life. The car owner must remember that if there is a desire to avoid premature wear, it is necessary to protect the brake pads from contact with water, engine oil, aggressive fluids such as antifreeze or brake fluid, as well as excessive overheating.
When braking efficiency drops, a squealing sound occurs when you press the pedal, the lining is completely worn out and the vehicle is slowed down only by the metal base - this is a sure sign of pad wear. Replacement required.
Car enthusiasts should not forget that the safety of the car, driver, and passengers in the cabin largely depends on the condition of the brake pads. Every vehicle owner should know when a replacement is required. However, the service life of such consumables directly depends on the material used in their manufacture, the individual driving style of the car owner, as well as operating conditions.
To maintain the braking system in working condition, you need to carefully monitor its performance. Experienced auto mechanics who work in specialized auto repair shops know exactly when it is necessary to change pads of one type or another. The remaining resource can be approximately determined by paying attention to the mileage of a particular car. Moreover, you can obtain information about the timing of replacement if you read the documentation included with the car.
The type of brake also affects the rate of wear. On average, brake pads are recommended to be replaced after traveling from 50 to 80 thousand km. You can extend the service life of such consumables by adjusting your individual driving style (sharp acceleration and deceleration while driving increases the rate of destruction of the linings several times).
The absent-mindedness of the car enthusiast can bring the day of replacing the pads closer. The fact is that inexperienced drivers (most often those who “got behind the wheel” recently) forget to release the car’s parking brake and start driving with the handbrake on. Such a “misconduct” has a very negative impact on the condition of the consumable material, as well as the performance of the braking system as a whole.
To increase the service life of the pads and prevent unnecessary costs associated with frequent replacement of this consumable, it is not recommended to perform long braking, which involves holding the brake pedal down for a long time. Experienced drivers in such a situation prefer to slow down their car by frequently and briefly pressing the brake pedal. Such measures will not only help prevent rapid wear of the pads, but will also prevent the car from skidding (the danger of such a phenomenon occurs when driving on a too steep slope or slippery surface), which will significantly increase the safety of the car, as it will prevent skidding.
How to determine wear?
Is an integral part of the periodic Maintenance. To understand how much this consumable has worn out during operation, you need to perform several operations in the following algorithm:
- Check for brake dust mixed with metal shavings on the wheel rims.
- Determine how effectively the braking system functions. Severe levels of wear can be indicated by the vehicle decelerating too quickly or ineffectively, as well as by the presence of a wobble when the pedal is pressed.
- Set the car to inspection hole or a jack. This will help facilitate the process of checking the functionality of the front brakes.
- Unscrew the front wheels using a telescopic spanner. If you are checking the pads on the left side, then you need to turn the steering wheel to the left (the same with the right side).
- Determine the thickness of the brake pad linings. This can be done by using the inspection hole, which is located in the movable caliper bracket. When carrying out this procedure, it is necessary to remember that if the thickness of the friction lining is less than 1.5 mm, then replacement is required.
- Place a jack under the rear wheels, then dismantle them and remove the brake drum.
- Measure the thickness of the friction linings using a caliper or an ordinary ruler. In addition to the small thickness of the linings, replacement is required if they are poorly connected to the base or oil traces were found during the inspection.
To check correctly, you need to prepare necessary tools, namely a jack, a telescopic wrench, a caliper, the functions of which can be performed by a regular ruler. This procedure does not require any special knowledge or extensive experience. To determine the need for replacement, a car enthusiast must have only basic skills and a general understanding of the work algorithm.
However, inexperienced car owners who have never had to check pad wear are not recommended to carry out such a check “alone”. The fact is that if the wear level of consumables is determined incorrectly, this may lead to a decrease in the effectiveness of the brakes or failure of the entire system at the most inopportune moment. The best solution in such a situation is to carry out diagnostics in a specialized car service center. Specialists will be able to quickly check and, if necessary, replace consumables.
How to choose the right brake pads?
When purchasing brake pads for your car, you must pay attention to the type of material from which the friction linings are made. Today on the market you can find the following types of linings:
- Metal. They are often made from steel or cast iron. In addition to automobile braking systems, a similar type is used in railway transport due to the provision of highly effective braking. Such material does not warp, but sharply loses its properties at temperatures above 400 degrees.
- Non-metallic. Such linings are made on an asbestos base, and resin or rubber is used as connecting elements. This consumable provides a high coefficient of friction until the temperature rises above 220 degrees.
- Sintered. This variety is most often produced on a steel base, but other materials are “sintered” with it during the welding process. Their role is played by pre-made blanks, which consist of powder mixtures subjected to strong heating. The performance properties of such consumables include a high coefficient of friction, wear resistance, stability, and good level adhesion.
Each type of consumable has unique properties that must be taken into account when purchasing.
Brake pads must be selected taking into account factors that influence wear. These include:
- Brand of consumables. Each manufacturer's pads have their own characteristics, which must be carefully studied and taken into account when purchasing.
- Vehicle weight. The heavier the car, the more force the brake system will need to exert to slow down or bring the car to a complete stop.
- Driver experience and individual driving style. Even an inactive car enthusiast can quickly exhaust the life of the pads. This happens when the driver does not know how to “brake with the engine” if necessary, or while idling in a traffic jam, keeps his foot on the pedal all the time and brakes sharply, approaching close to the car in front.
If a car enthusiast is accustomed to “aggressive” driving, then it is worth giving preference to consumables with increased wear resistance when working under harsh operating conditions (when the temperature at the friction point rises to 1000 degrees). Such pads, as a rule, are made of expensive materials, which has a significant impact on the cost of the finished product. If there are not enough funds to purchase such pads, then all that remains is to adjust your driving style.
Preparing the car for replacing brake pads
Before replacing the pads, it is necessary to prepare two types of lubricants, namely for processing the studs and the hub pad, for lubricating the guide pins and brackets that serve as pad retainers. If it is necessary to process the studs and the hub pad, then most often a graphite type of lubricant is used. However, it is possible to use a high temperature type made on a copper base. The fact is that a copper dab can more effectively protect metal surfaces from wear, oxidation, and “sticking” under extreme temperatures (from -40 to +1100 degrees).
The second type of lubricant required for the guide pins and retaining brackets should be a general purpose lubricant (preferably). Such a lubricant can effectively perform its functions, moreover, it costs much less. Before you start lifting the car with a jack, you need to select as level a horizontal surface as possible, put the car in neutral gear, sharply press the brake pedal, and then immediately release it. The last action will allow you to “deepen” the brake piston, which will make further actions easier.
It is necessary to place special stops under the wheels to prevent accidental movement of the vehicle during maintenance. To make it easier to “recess” the piston, you need to open the hood and unscrew the cap of the reservoir that contains the brake fluid. To gain access to the pads, the wheel must be removed. You need to fix the guide pin using a 17mm wrench, then unscrew the lower and upper fixing bolts.
Some car enthusiasts, when replacing pads in a personal garage, prefer to completely unscrew only the lower fixing bolt, and simply loosen the upper one, so that in the future they can lift the caliper up and not completely dismantle it. Using this method of maintenance, you can significantly speed up the process, but it is impossible to check the stroke of the guide pin in such a situation.
In specialized car services, where the quality of service delivery is always put first, rather than the speed of completion of maintenance, the caliper is always completely dismantled. This approach allows for more efficient inspection and replacement, and, moreover, saves the car owner from “unpleasant surprises” on the road. To prevent the caliper from interfering with maintenance, specialists often hang it using a metal wire on the suspension spring.
What tools are needed to replace brake pads yourself?
Before you begin to “prepare” the car for the replacement procedure, you need to collect the necessary tools and other things. These include:
- Manual. If a car owner replaces the pads himself, then he needs to make sure that such a manual is available. If the “book” purchased with the car is not compiled in detail, then you need to purchase a higher quality edition with detailed step-by-step instructions. Such a guide will be useful to car enthusiasts who have little experience, as it will help to accurately determine the installation location of the jack, supports for holding the vehicle suspended, and obtain other information for the replacement procedure.
- Jack. As a rule, it comes with a new car. The jacks provided by the manufacturer are ideal for replacing a wheel, but “original” jacks are not always suitable for dismantling the pads. The fact is that they often cannot lift more than half the weight of the entire car, since the manufacturer believes that such a load capacity is quite enough to replace a wheel. But to replace the pads you need a device that can lift up to ¾ of the car’s weight. If we are talking about a passenger car, then correct solution- purchase a jack designed for 3 tons. This will ensure safety and lift heavier machines if necessary.
- Lifting support. It is required to keep the car stable in the air after it has been lifted using a jack. Each such “stand” has individual load-carrying characteristics, so you need to purchase them based on the total weight of your personal vehicle. The best solution is to buy products with a reserve carrying capacity.
- Caliper adjustment tool. It makes it possible to independently calibrate the caliper if necessary. It can be done in other ways, but often all of them are less effective, especially if the car enthusiast lacks experience.
- New pads and brake discs (if necessary). An experienced car enthusiast will always prepare consumables in advance to replace worn ones before dismantling the wheel and removing old pads.
- Brake lube. It must be prepared, as it is needed for applying new pads and calipers to the surfaces during reassembly.
- Set of socket and wheel wrenches.
By preparing the listed tools and materials in advance, the car enthusiast will speed up the replacement procedure as much as possible.
Step-by-step instructions for replacing brake pads yourself
Inexperienced car enthusiasts often ask: how to understand brake pads. They should know that the replacement process in disk and drum systems has its own characteristics that need to be studied in detail before starting the procedure. If we are talking about replacing worn brake pads in a disc system, then you need to adhere to the following algorithm:
- Jack up the car, remove the wheel, and then install a special support on the bottom.
- Unscrew the caliper guides. If the design contains fixing brackets, they must be removed using a screwdriver.
- Disconnect the pad wear sensor connector, if equipped.
- Remove the pads from the disc using a screwdriver. This action is performed to press the brake piston.
- Remove old consumables.
- Install new pads.
- Reassemble the brake system in the reverse order, that is, put the wheel “in place” and remove the jack.
- Bleed the brakes. This is necessary for the new pads to “break in”.
Carrying out the above steps in the described sequence will help you carry out the replacement procedure as efficiently as possible and achieve a positive result without resorting to the help of specialists.
If the car is equipped with a drum brake system, the replacement procedure will have some differences. Actions are performed in the following algorithm:
- Jack up the car, install a support under the bottom and be sure to remove the car from the handbrake.
- Unscrew the bolts securing the brake drum, and then dismantle it.
- Release the handbrake cable. To do this, you will need to dismantle all the springs and remove the rear brake rods.
- Remove old pads.
- Install new brake pads, then reassemble the entire system in reverse order.
- Reinstall the removed wheel without removing the car from the jack.
- Check the operation of the rear brake mechanism. To do this, you need to put the car on the handbrake and try to spin the wheel.
- Pull the jack and supports out from under the car.
The described algorithms cannot be called complex - all actions can be performed in a personal garage by the car owner. However, a car enthusiast should have at least a general understanding of the design of the brake system (disc or drum). If there is no minimum experience and knowledge, then “climb” replace brake pads, “armed” with one instruction is not recommended. An incorrectly assembled brake system may not work at the most inopportune moment.
Running in brake pads after replacement
Often, after replacing the pads on their own, car enthusiasts forget to break in the new consumables and immediately begin to operate the brake system in “aggressive” mode. Such an attitude can most likely lead to premature failure of the brake system elements (and we’re not just talking about the pads). Such use provokes the appearance of a “whistle” when braking in 80% of cases.
To increase the service life of the brakes, it is necessary to run in, adhering to the following algorithm:
- Warm up the brake system. To do this, without starting to move, press the brake pedal several times (2–3 times). This will help create the right pressure.
- Start driving using intermittent braking for the first 300 km. In this case, you must avoid pressing the pedal hard or for long periods of time. Such “procedures” make it possible to prevent the pads from overheating immediately after installation. During break-in, you need to pay attention to strong noises and vibrations that occur when the brake system is activated. The presence of such phenomena may indicate improper assembly or installation of brake system components. If such “symptoms” occur, you will need to check it yourself as soon as possible or contact the car service center where the replacement was made. Supplies.
- Perform final run-in. After passing the first 300 km, 3 to 5 intensive braking sessions are required. Such braking must begin at a speed of 90 to 110 km/h. The initial force when pressing the pedal should be average, then it needs to be increased until it comes to a complete stop (you don’t have to do this: just slow down as much as possible). Between intensive braking, you need to allow the system to cool for 1 minute.
- After the initial break-in and a series of intense braking, drive for several kilometers and try not to use the brake at all. This is necessary to cool the brake system as much as possible.
Running in is carried out in order to prepare the material from which the pads are made to the high temperatures that occur at the friction point during braking. Carrying out the described “procedures” allows you to avoid temperature shock (it provokes rapid wear) and effectively grind in the working surfaces of the pads and brake discs.
To perform the break-in, you need to have a certain experience, in the absence of which, entrusting the described procedure to a more experienced specialist is the best solution. This will help avoid damage to the brake system when performing “rough” break-in.
Possible problems and their causes
As mentioned above, if the installation of new pads is carried out by an inexperienced car enthusiast, then problems may arise during future operation. These include:
- Overheating of brake discs. The main reason for this is the “wedging” of the caliper guides. In such a situation, the pad cannot fully interact with the working surface of the disc. Uneven pressure resulting from deformation of the pad leads to overheating. Its premature wear can also be a cause.
- Creaking and grinding of pads. The reason for the appearance of such sounds during operation of the brake system may be a violation of the integrity of the boot of the main piston, the use of low-quality consumables, the absence of cuts or bevels on the surface of the pad, excessive overheating of the disc or its wear. Extraneous noise can be eliminated different ways depending on specific reasons.
- “Sinking” of the brake pedal. This phenomenon can be caused by damage to the cylinders, a lack of working fluid in the system, or poor-quality assembly. Most often, the pedal fails after replacing the pads due to the carelessness of the car enthusiast who installed them. Inexperienced intervention in the system will most likely cause air to enter or working fluid to leak out.
- Knock when braking. It can be caused by play in the caliper guides, wedging of the piston, bending of the brake disc, or loosening of the cable in the parking brake system. Another reason for the appearance of such extraneous noise can be the anti-lock braking system, if it is included in the design. To check this, you need to pull the fuse from it, which will “turn off” the ABS, but the brakes will continue to function.
- Vibration. It may be caused by deformation of the brake disc. It may be caused by excessive heat during operation. The fact is that during intense braking, the pads can be pressed too hard against the disc, creating enormous pressure and temperature. This can cause the disk to lose density and change its shape. It is worth noting that sudden cooling of the disk can also cause deformation in certain places.
Taking into account the above reasons, you can adjust your driving style in such a way that the service life of discs, pads and other elements of the brake system will increase several times. An inexperienced driver can protect the braking system from such problems to some extent by installing ABS.
Brake pads are an important part of the car's braking system, responsible for reducing the vehicle's speed when necessary. The safety of the driver and passengers depends on the quality and performance of brake pads, so every driver should know what replacing brake pads is and how to maintain the performance of the brake system. This is a simple procedure, so it will not be difficult for motorists to replace the pads with their own hands.
All parts in a car have a certain working life, which decreases during operation. Brake pad wear is influenced by various factors, so the frequency of replacement may vary in each individual case. How to replace brake pads and what is needed for this - all this will be discussed in this article.
Most of passenger cars equipped with disc brakes, but some still have drums (eg Toyota Prius). When you press the brake pedal, the friction surface of the pads comes into contact with the disc, causing its movement to slow down. In the case of drum brakes, everything happens in a similar way, only the linings are pressed not from both sides, as is the case with a disc, but from the inside of the drum. As soon as the driver releases the pedal, the pads automatically return to their original position.
How does a car's braking system work?
The friction surface gradually wears out, as a result of which the system cannot slow down the vehicle. A faulty braking system puts the lives of the driver, passengers and other road users at risk. Therefore, you need to change the pads in a timely manner, without postponing this matter for later.
Why do pads wear out?
The following factors can affect how long your brake pads last:
- quality of previously performed pad replacement;
- climatic conditions of your region;
- manufacturing company;
- cost of the part;
- features of driving a car;
- quality of the road surface.
Brake pad wear On a note! It is recommended to check the operation of the brake system every 10,000 km. During the inspection, you need to pay special attention to the brake pads and their behavior when you press the brake pedal. If creaks or other third-party sounds appear, damaged elements must be replaced.
Despite the various factors influencing the frequency of replacing brake pads, there are average data. If you own a domestic car, then you need to change the pads every 15,000 km. In the case of foreign cars, these indicators differ significantly and replacement is recommended every 20,000 km. If we are talking about racing cars, then replacement needs to be carried out much more often (approximately every 5,000 km).
The wear of the front brake pads is more intense than the rear ones, so they need to be changed several times more often. There is also a significant difference between operating a car with disc and drum brakes. If the average frequency of replacing pads for disc brakes is 10,000-20,000 km, then for drum brakes it is 120,000 km. But these figures may vary depending on several factors mentioned above.
Main signs of wear
The car's braking system works non-stop, so over time, some of its components may fail. But most often, system malfunctions occur as a result of pad wear. There are several signs that help motorists determine whether their rear or front brake pads are worn out.
Braking distance increases
If you suddenly notice that the braking distance has sharply increased, this may indicate the need to replace the pads or other elements of the system. As practice shows, an increase in brake pressure can be caused by damage to the brake caliper or wear of the friction surface of the pads.
Uneven frictional wear of pads
If the pads on one axle wear out more than the other, this most likely indicates that the brake caliper needs to be replaced because it is not functioning properly. Untimely replacement of the caliper will lead to the fact that even the most expensive and new pads will fail quite quickly.
Uneven brake pad wear Integrity violation
The presence of mechanical damage, which is visible even with the naked eye, indicates the need to replace damaged parts. Most often, drivers encounter damage to brake discs, chipping of parts of the friction material from the pad, severe abrasions or cracks.
Large free travel of the brake pedal
Severe wear of the brake pads can be determined by the force that must be applied to press the pads to the surface of the disc. In this case, the brake pedal must be pressed with greater force, which the driver notices almost immediately, as well as the increased travel of the pedal itself.
Lost brake fluid
During operation, when the pads gradually wear out, an increase in brake fluid consumption is noticed. This is due to the fact that the brake caliper is forced to work with great force to press the pad to the surface of the disc. This operation requires more pressure and, accordingly, more brake fluid. This leads to a rapid decrease in its level in the system.
Triggering a special signal
Some car models are equipped with a special sensor that alerts the driver when the brake pad is worn thin. You can find out about this by hearing a characteristic sound or seeing a warning light come on. If this happens, you should replace the pads as soon as possible.
What is needed for replacement
Before changing the brake pads, you need to prepare all the tools:
- C-shaped clamp;
- a set of wrenches (they will be needed to remove the wheel and loosen the brake caliper);
- work gloves;
- jack;
- pliers;
- screwdriver;
- safety glasses to protect your eyes from chemicals;
- a respirator may also be required to protect you from inhaling harmful brake dust;
- set of new brake pads.
Tools for replacing brake pads Most of the above tools should be kept in every motorist's garage, so you don't need to be a born mechanic and have special equipment to replace brake pads, whether you have a VAZ 2101-21099 or a Renault Logan.
If there are no problems with preparing the tools, then when choosing a set of brake pads you may encounter some difficulties. First of all, this is due to the large number of manufacturers.
What to pay attention to
There are a few important points that need to be taken into account when choosing brake pads. These are the originality of the parts, the quality of the packaging, as well as the operational features of the pads.
Originality of details
The automobile market is filled with various counterfeits that unscrupulous sellers are trying to sell to drivers under the guise of original products. Moreover, it is not always possible to determine a fake by cost. This requires practice or special skills to identify a copy. For this purpose, there is a large amount of information on the Internet, which indicates the main methods for distinguishing original parts from fakes. Spend 30 minutes of your free time researching information about your pads.
Buy only original brake pads If there is such an opportunity, then you need to make purchases only in trusted specialized stores. This will help protect against low-quality products.
Product packaging
When choosing pads directly in the store, try to study the packaging in detail. Read all the inscriptions (evenness of the written lines and correct spelling of all words), pay attention to the design of the packaging. It would also be a good idea to unpack it and inspect the pads themselves for mechanical damage and other defects. Make sure that the serial number on the box matches the number on the pads themselves.
Study the information on the brake pad box Operational Features
If you are a fan of fast driving, then you need to select the appropriate pads. There are special brake pads that are designed for use in urban conditions, in mountainous areas or for sports driving.
Manufacturers rating
Having decided on the type of brake pads that suits you best, all that remains is to choose a manufacturer. We will try to help you with this. Below is a list of well-known brands of brake pads for domestic and foreign cars.
Table. Review of the best brake pad manufacturers.
| Brand name | Description |
|---|---|
 ABS | European manufacturer of automobile brake parts, considered one of the best in the world. The company produces products not only for cars, but also for trucks, covering a range of vehicles made in America, Korea, Japan and Europe. |
 | It is rightfully considered a leader in its field. Allied Nippon is recognized the best manufacturer brake pads for imported cars. Thanks to the mineral metal used in production, the pads have an increased coefficient of friction. |
 ATE | ATE products have a long service life, which makes them one of the best in terms of economy and reliability. Brake pads function effectively in various weather and temperature conditions. |
 | In the manufacture of brake pads were used Newest technologies, which ensured optimal braking under different conditions. Ferodo Target is the ideal combination of price and quality, which is why many motorists prefer the products of this brand. |
 Bosch | The friction material of Bosch brake pads includes mineral wool, carbon fiber, aluminum, copper, natural rubber and other components, which makes them resistant to temperature and other external factors. The products of this brand meet all standards for wear resistance, stability and uniformity of characteristics. |
 Samko | An Italian manufacturer that managed to conquer the whole world. The friction material of the brake pads does not contain asbestos, which makes them unique in their kind. The products are characterized by quiet operation, thermal stability and minimal abrasiveness. In addition, the friction coefficient of the pads does not change with increasing temperature, as can happen with some analogues. |
On a note! You cannot skimp on safety, so when choosing brake pads, give preference not to the cost of the product, but to its quality. Low-grade brake pads are made from cheap components, which significantly reduces the efficiency of the system.
Getting started with the process
Replacing brake pads will cost a motorist much less than visiting a car service center, which usually results in a serious hit to the wallet. To correctly perform this procedure at home, you need to follow step by step instructions listed below.
Removing old pads
Step 1. Buy quality brake pads. They are available at any auto parts store or local car dealership. Just give it to the manager necessary information about your car (year of manufacture, car model and the approximate cost of the product that you expect). In general, the more expensive the pads, the longer they will last you.
Step 2. Make sure the car is cool. If you just drove it home from work or the store, you risk being seriously burned by hot pads or calipers. Make sure these parts are thoroughly cooled before replacing them.
Step 3. Loosen the nuts. Using a wrench, loosen each of the nuts that secure the wheels. Unscrew them about 70%. Do not loosen all wheels at the same time. As a rule, when replacing brake pads, 2 front or two rear pads are replaced. This depends on your vehicle and how evenly the running surface is worn. So either start from the front or the back.
Step 4. Carefully raise the vehicle with a jack until it is raised enough to work. Check your owner's manual to determine the correct jack position under your vehicle. Place several wheel chocks behind the other wheels to prevent the vehicle from moving when changing.
Step 5. You can start removing the wheels. Finish unscrewing the locking nuts only when your vehicle is in a raised position. Pull the wheel slightly towards you to remove it.
Step 6. Select the correct size wrench to remove the brake caliper bolts. The main task of the brake caliper is to forcefully create adhesion between the friction surface of the pads and the disc. Typically, calipers are attached to the vehicle's hub using 2 or 4 bolts. If necessary, use WD-40 if you have trouble getting the locking nuts off.
Take the opportunity to check the functionality of your brake calipers. To do this, move them slightly from side to side while at rest. But here you need to be careful, even though the fasteners are not completely unscrewed.
Step 7 Carefully hang the brake caliper on the wheel well as shown in the picture. Use a small piece of wire to hang the caliper. This way you can protect the flexible brake hose from being pinched.
Replacing elements
Step 1. It's time to remove the old brake pads, but first you need to remember the position in which each of them was secured. As a rule, the pads can be secured using a special metal latch. After removing the pads, you need to conduct a visual inspection of the brake disc. Pay attention to any cracks or chips. Many manufacturers recommend replacing brake discs along with the linings.
Step 2. Install new pads. At this point, you can apply lubricant to the metal edges of the brake pads. This will avoid squeaks when braking. Avoid getting lubricant on the working surface of the pads, as this may reduce the effectiveness of the vehicle's braking system. Install new elements in reverse order.
Step 3. Check the brake fluid level on your vehicle and add some if necessary. Screw on the brake fluid reservoir cap when finished.
Step 4. Reinstall the brake caliper. Carefully place the caliper back onto the brake disc, being careful not to hit or damage anything. After this, screw in and securely tighten the retaining bolts that hold the caliper in place by hand.
Now you need to reinstall the brake caliper Step 5. Reinstall the wheel. Place the wheel and tighten the lug nuts. Only after this can the car be lowered to the ground.
Step 6. Tighten the wheel nuts until they are tight. Once the car is on the ground, begin tightening the opposite nuts. This will improve the reliability of the wheel fastening. Read the car's operating manual. There should be information about the force that must be applied when tightening the nut (tightening torque). To measure it you will need a torque wrench.
Tighten the wheel nuts fully Step 7 Start the car. After making sure that the car is on the handbrake, pump the brakes by pressing them 15-20 times. This will help you ensure that the pads have been installed correctly.
Step 8 Check new brake pads. Moving at a speed of no more than 10 km/h, gently press the brake pedal. If the car stops normally, repeat the test at 20 km/h. Repeat several more times, gradually increasing the speed to 60 km/h. After this, check the operation of the brake pads while driving in reverse gear. This will speed up the process of the new pads adhering to the brake disc.
On a note! Pay attention to sounds as you move. After installation, new brake pads may squeak a little, this is normal. But if you hear a metallic grinding sound when braking, then most likely you have installed the pads incorrectly. Rearrange them as soon as possible.
Bleeding the brakes
Step 1. Unscrew the cap from the brake cylinder reservoir. Under the influence of the environment, the brake fluid becomes contaminated during operation (dirt, dust, moisture gets there). All this negatively affects the properties of the liquid, which causes its boiling point to decrease. Be sure to drain the fluid if you are replacing brake pads or calipers. But, no matter how ironic it may sound, during the replacement process you may need this fluid, so you need to drain it from the brake calipers themselves, and you need to leave a little in the reservoir.
Step 2. Drain the brake fluid sequentially. You need to start on the side that is furthest from the tank. Be sure to check the car's operating instructions, since all car models are different in this regard. If you have any questions or cannot find the instructions, then consult your auto parts store salesperson.
Step 3. Attach a plastic hose to the nipple, which acts as a drain hole for the brake fluid. Place the other end of the hose into a small bottle or pan to drain the liquid. To prevent air from returning back into the system, you need to hang or hold the bottle above the level of the calipers.
Step 4. Have an assistant press the brake pedal. With the engine off, have your friend continually pump the brakes until he feels resistance. After this, he should notify you so that you know about the appearance of resistance. After this, you need to slightly unscrew the fitting.
At this point, the liquid should be drained into a bottle or pan. Screw the drain screw back in when your friend's foot touches the floor. Repeat this process until you see air bubbles in the tube.
Step 5. Double check the system for air bubbles. If squeezing the brake pedal is accompanied by bubbling of fluid in the master cylinder, then there are still air bubbles in the system. Start draining it again before you drive.
Turn the vehicle's steering wheel so that the front wheel is pointed outward. This will greatly facilitate the procedure for replacing brake pads due to increased access for work.
If you are changing the brake pads on the rear wheels, be careful when working around the parking brake system. Be extremely careful when removing and adjusting. Inspect the brake rotors for wear and rust. These two symptoms can lead to squeaking pads when braking.
Important points
When replacing, you need to take into account some nuances. This will avoid common mistakes that beginners often encounter.
- Always use stands when jacking up the car and place wheel chocks or regular bricks under the wheels. This will prevent the machine from moving when changing the pads. In this case, you should not completely rely on the work of the jack.
- Avoid contact of the lubricant with the surface of the brake pad. If this does happen, the system will cease to create the necessary friction and will become practically useless.
- Do not remove the brake hose from the caliper. This can cause air to enter the system and cause it to stop functioning properly.
We hope our article was useful to you and you were able to change the brake pads yourself. Neither a nail nor a rod, dear motorists!
Video - Replacing brake pads on a VAZ 2108, 2109
Any equipment must be protected by caring for it, using it correctly and repairing it in a timely manner. An integral part of the maintenance procedure is checking the condition brake system.
On modern cars, this is a whole range of work, including visual and sometimes computer diagnostics. However, the need for replacing brake pads may occur either earlier or later than the next maintenance date.
Many factors influence friction lining wear:
- The mode in which the vehicle is operated. When driving in dense city traffic, where you often have to stop at intersections, traffic lights, or simply in traffic jams, wear occurs much faster than on free country roads.
- Driver's driving style. Car owners who prefer a calm driving style have to think about brake maintenance much less often than fans of an aggressive driving style.
- Climatic conditions. At high ambient temperatures, the load on the braking system increases.
- Dirt falling on the surface of the linings, discs and drums, souring of caliper pistons or cylinders - all this also significantly reduces the service life of parts.
Taking into account the listed factors, it is almost impossible to accurately answer the question of when to change brake pads, indicating the mileage or period of operation.
The main thing is control
Realizing the importance of the problem, many developers install brake wear sensors pads
Sensors come in different types:
- Electronic devices, transmitting information to the on-board computer or signaling wear by a lamp that lights up on the instrument panel.
- Mechanical. In this case, the driver learns that it is time to visit the service center by a characteristic sound. Most often this is a crackling noise heard in the area of the wheels.
But there are cars on which similar systems there are no controls. In this case, you can only rely on visual inspection data.
To do this, some manufacturers make a special slot in the lining material. In any case, the thickness of the lining must be at least 2 mm. Otherwise, you risk simply damaging the surface of the disk, and the critical part will require urgent replacement.
Features of choice
Before you go to a store or workshop, it is important to answer another question: which brake pads are best to choose? After all, there are many manufacturers specializing in the production of these critical components.
To avoid getting into trouble, you need to understand the following:
1. Under no circumstances should friction linings contain asbestos.
2. There are no pure polymer or ceramic brake pads. Most companies develop their own friction mass recipes, which can contain 20 or more components.
Information about the exact chemical composition often kept secret. The presence of large fragmentary inclusions in it indicates the low quality of the part, and added by some manufacturers metal shavings will extend the life of the linings, but will kill discs and drums in a short time.
The reason is simple: initially, the characteristics of the friction linings are selected in accordance with the parameters of the discs or drums.
In any case, you should give preference to products from well-known brands with a proven reputation.
Replacement of front brake pads. Video:
Replacing front brake pads
Since the load on the elements of the brake system of the front axle of the car is much higher, they have to be serviced more often.
The difference in kilometers traveled can be quite significant - two or more times.
Most modern cars have disc brakes installed at the front.
We will consider this case when answering the question of how to change brake pads. The sequence of actions is as follows:
1. Loosen the bolts of the wheels being serviced.
2. We hang out one of the car wheels. When you have a lift at your disposal, you can lift the entire car. If not, you will have to use a jack, securing the rear wheels with chocks for safety. It makes sense to install an additional support under the car for insurance.
3. Completely unscrew the bolts and remove the wheel. There may be further options, each of which we will consider separately:
4. Remove one of the pads. After that, arm yourself with a flat pry bar. Inserting the tool into the space with the piston and the back of the pad, push the piston into the caliper.
If the pistons are located on both sides ( There are also such systems), then you will have to repeat this operation in a mirror way. At the same time, try not to press on the surface of the disk so as not to damage it.
5. Check the integrity of the boots on the pistons. If they are damaged, be sure to replace them. Make sure there are no brake fluid leaks on the mechanism parts and hoses.
6. Make sure that the disc is not damaged or worn beyond acceptable limits.
Degrease its working surface. This can be done with gasoline or alcohol.
After this, install new parts and reassemble in reverse order. Some manufacturers sell a special lapping compound along with the pads. It will have to be applied in a thin layer to the work surface ( rubbing against the disc) surface of the overlays.
7. Press the brake pedal several times, so that all the details fall into place.
8. Reinstall and tighten the wheel. After this, repeat all the above operations on the other wheel. Which one to start with – left or right – doesn’t really matter. Remember that you must act carefully so as not to damage the brake system parts.
Replacing rear brake pads
If disc brakes are installed on the rear axle of your car, the replacement process will be the same as for the front wheels.
How to change rear brake pads when dealing with a drum system? Proceed in the following sequence:
How to choose good front brake pads? Video:
Important!
After replacing the brake pads, it will take some time for the linings to get used to the drums. During this period, braking performance will be lower than usual.
It makes sense to drive through a safe area for several kilometers at low speed, accelerating and braking.
Possible problems
On paper everything is smooth. But it is possible that after completing the above work, certain problems may arise. We will try to mention the most common problems, possible causes of their occurrence and methods of elimination.
1. Brake discs get hot after replacing pads. Depending on the design brake system, the reasons may be different:
- Disc brakes tend to get hot due to souring of the calipers. This could be either souring of the floating caliper bracket itself or of the pistons pressing on the pads. The problem can be solved by removing corrosion from the parts and, as experts say, “rocking the calipers”, ensuring the free movement of their components.
- Drum brakes get hot for other reasons. The most probable are incorrectly installed pads or a groove in the form of a side formed on work surface drum The wear must be removed by turning the part to lathe. If this is not possible, you will have to install a new drum.
In both cases, the cause of the malfunction may be poor-quality brake pads, whose size does not correspond to the standard one. This, unfortunately, happens.
Another reason - compensation hole clogged in the master cylinder, causing excess pressure in the brake circuits. Dirt from the hole will have to be removed.
2. The pads squeak when braking. This does not always affect the efficiency of the car's braking system, but it will certainly irritate the driver and passengers.
To understand why the pads squeak, you will have to return to the section that lists the features of the device and the selection of these parts.
Most often, the reason lies in the incompatibility of the material of the friction linings and the metal from which the brake discs or drums are made. In this case, resonant vibrations occur at the point of contact of the parts, which become the cause of an annoying squeak.
Buy pads and discs from the same manufacturer, and you will get rid of squeaking.
The cause of the problem may also be improper operation of the brake mechanisms due to wear of some parts.
In this case, it is possible to bring everything back to normal by purchasing and installing it, which includes springs, guides and spacer bars.
But we cannot exclude the possibility of a pressure difference in the brake system circuits. This happens if air or dirt gets in there. Replace the brake fluid and remove the air.
In any case, remember that it requires certain skills and patience.
You won't be able to do the job yourself if you don't have a quality tool.
People who doubt their abilities should contact a service station, entrusting the solution to their problems to professionals. After all, we are not talking about the brakes, but, therefore, about your safety.
Every car owner should understand that proper operation of the brakes is the key to the safety of the driver and passengers while driving. The correct operation of the brake system depends on many factors, but first of all you should pay attention to the condition of the brake pads. The wear of the pads is determined by the remainder of the friction part, that is, the material on the main part of the pads with which they are pressed against the plates. This is the part that is prone to wear.
Brake pads are one of the most frequently worn parts of a car, so every car enthusiast sooner or later should learn how to change brake pads without the help of specialists.
Front brake pads and rear brake pads must be changed in pairs, that is, it is not recommended to change them on one front wheel and leave the old ones on the other. Same with the rear wheels. This causes the car to destabilize during braking.
Choosing brake pads for a car
Of course, longer operation of the braking system depends on the correct choice of brake pads. Here you can’t save money and chase cheapness. Moreover, cheap, low-quality pads can ruin brake discs, leaving dents on them during braking, and replacing brake discs is a more complex and expensive process than replacing pads.
However, the high cost of these spare parts also does not guarantee quality. Most best option, visit the car manufacturer's website and find out exactly what pads were used when your car model was produced. They will work longer than pads from other manufacturers, since the developers took everything into account design features car and used the most suitable materials.
Preparing to replace brake pads
Before replacing the pads with your own hands, you need to prepare the tool:
- jack for raising a car;
- wheel wrench for wheel removal;
- pliers;
- a thin lance about ten centimeters long;
- a large screwdriver.
In order to start replacing brake pads, you need to secure the car with a parking brake or place some kind of block or brick under the wheel, which will prevent the car from moving. Then you need to slightly lift the car with a jack and loosen the bolts on the wheel with a wheel wrench. You need to lift the car until the wheel touches the ground and does not turn when the bolts are unscrewed. After the bolts are loosened, you need to jack up the car until the wheel leaves the ground.
After this, the bolts are unscrewed with a wheel wrench and the wheel is removed from the hub. Then, depending on the side on which the pads are being changed, you need to turn the steering wheel in the desired direction: if the replacement is made on the left, then to the right, and if on the right, then to the left.
Then you need to use pliers to remove the locking pins from the guide pins and use a pick to knock the pins out of their seat. Afterwards you need to remove the springs if they did not fall out when removing the fingers. Next, by pressing on the moving part of the caliper with a large flat screwdriver, you need to increase the distance between the brake disc and the pads. You need to remove the old brake pads from the resulting gap and install new ones in the same position.
To reassemble this part of the brake system, you need to perform all the above steps in reverse order.
Knowing how to replace brake pads on one wheel, you can perform all of the above steps on the remaining wheels.
Important points in the pad replacement procedure
- Before replacing the pads, you need to check the brake fluid reservoir. There is no need for it to be full to capacity, because... When the moving parts of the caliper move apart, fluid may spill out, which will damage the car's paint.
- Before lifting the car with a jack, it is necessary to open the driver's door window, because When lifted, the body may shift slightly, and this will prevent the door from opening.
- Because When disassembling the brake pad alignment system, many small metal parts are formed, it would be prudent to use a magnet to store them and prevent the loss of any element.
- Rust may accumulate in the seat of the guide pins, which will make their removal difficult, so you need to spray a special liquid there in advance.
- When installing all the elements back, it is recommended to clean them from dirt and dust and spray them with graphite lubricant. This will make it easier to replace the brake pads later.
Diagnostics of the work done
Before you take your car on the road after replacing the pads, you need to perform some diagnostic steps. First, you should visually inspect the pads and wheels to check that they are installed correctly and that there are no brake fluid leaks.
Then, after sitting behind the wheel, you need to press the brake pedal several times until the pedal slip disappears. This is necessary to bring the pads to the brake discs. Now you need to check how the car brakes while driving. There should be no destabilization when braking, i.e. During the braking distance, the car should move smoothly, without skidding in any direction.
The best test is acceleration and hard braking. It is recommended to carry out this check in an open area so as not to damage your car or the cars of other road users.
How often do you need to change brake pads?
As mentioned earlier, driving on worn pads is unsafe for the driver and passengers, so the car owner himself must monitor their condition. Professionals recommend changing all four pairs of pads at once, but practice shows that the front pads, due to the greater load on them, wear out faster than the rear ones.
Modern cars have indicators that detect pad wear and inform the driver about it. But, according to experts, any electronics can fail, and in this case it can lead to tragic results.
It is better to always check the wear of the brake pads yourself. To do this, turning the steering wheel in the right direction, you need to visually assess the remainder of the friction part on the pads. This is enough to understand whether the pads are worn out or not. Or you can contact the service.
As you can see, the procedure for replacing brake pads is quite simple, so, as they say, good luck!
Video
Replacing the pads on a VAZ is as follows:
In city traffic conditions, car brake pads work in extreme conditions. And if the owner also drives aggressively, then you don’t have to wonder why the pads have to be changed so often. Especially the front ones. Replacing front brake pads yourself is the topic of this master class.
1 Why are front pads repaired more often?
Try to count how many times you press the gas pedal while driving from home to work - you will be surprised. The brakes especially suffer for those who like to drive fast, and the front pads wear out especially quickly - firstly, they work faster than the rear ones, and secondly, when braking, the entire weight of the car presses on the wheels and brake discs.
It hardly needs saying that brake pads must be of high quality and there is no need to skimp when choosing them - high-quality spare parts can save your life in a difficult situation. And lovers of extreme driving should pay special attention to the degree of wear of the pads and change them much more often than the manufacturers recommend.
2 Front brake pad replacement period
Not a single manufacturer will tell you exactly the number of kilometers that a particular model of brake pads will last, so when purchasing, you should not think that they will last you for the specified kilometer. The packaging shows very average indicators. It is worth noting that each car brand has its own recommended pad replacement period. Most modern luxury cars have sensors on the brake discs. They are the ones who display information on the car’s on-board computer and notify about wear of the brake pads.
It is very important to observe the permissible wear thickness of the pads and not to exceed this value, because with further use the brake discs will wear out, which cost much more than complete replacement front brake pads. On average, during intense driving, high-quality pads fail after a year of use. For car owners who rarely use their vehicle, brake pads may last for several years.
It is very rare for front brake pads to wear unevenly. This depends on proper bleeding of the brakes after replacing the pads, as well as on the chassis of the car. When replacing the front pads, it is very important to properly bleed the car’s brakes, as well as monitor the amount of brake fluid, which will be discussed further.
3 Replacing brake pads with your own hands
The principle of replacing front brake pads for all makes and models of cars is almost the same and differs only in the type of brake mechanism. Front brake pads should be replaced on both wheels, even if one side is not worn as much. To replace the front pads, it is best to use an inspection hole.
Step 1. Preparatory stage
We position the car in the center of the overpass so that the sides of the wheels can be approached freely. Next, you need to put the car on the handbrake and put something under the rear wheels. After this, loosen the bolts on the wheel on the side where we will be replacing it, and lift the car on a jack so that the wheel rotates freely. After unscrewing the bolts, remove the wheel completely.
Step 2: Removing the brake pads
The hardest part at this stage is pushing out the brake piston, so additional effort may be required.
Step 3. Caliper
Next we proceed to disassembling the caliper. To do this, you need to unscrew the lower bolt securing it and remove the upper lock of the block. The upper caliper bolt does not need to be unscrewed, since it only serves as a fastener. After this, the car caliper should be raised to the upper position, as in the video; if necessary, use a pry bar. Next, you can safely remove the old brake pads.
We take out the pads
Step 4: Installing the pads
Before reassembling the brake mechanism, clean the caliper and lubricate its elements; the brake pads do not need to be lubricated. Next, install the pads in order in the caliper mechanism and secure them with new clips that come with the kit.
Step 5: Reassembly
After this, you need to return the upper part of the caliper to its original position and tighten the lower mounting bolt (without much effort). After replacing the brake pads, press the brake pedal in the car several times, then rotate the car's brake disc with your hands and check whether the pads are rubbing too much. If severe friction occurs, loosen the lower caliper mounting bolt slightly.
For ease of work, when replacing pads on the left side, turn the steering wheel to the left, and vice versa for the right side. Now you can begin reassembling the wheel and move on to replacing the pads on the other side of the car.
At the initial stage after replacing the front brake pads, a slight unpleasant sound may occur. It occurs if the pads are not of sufficient quality and goes away after they are ground in.
Before replacing the front brake pads, be sure to conduct a full inspection of the remaining brake mechanisms. It is necessary to make sure that the brake hoses are sufficiently clamped and secured with clips. On brake disc there should be no mechanical damage. You can also measure its thickness; for this you will need a caliper. The thickness of the disk should be the same on all sides, as in the video.