Brake pads - cheap to replace though crucial to life
Publié par Aaron Cremona le
A surprisingly large number of drivers threaten both their lives and others by driving a car with malfunctioning brakes. In order to avoid your brakes failing at a crucial moment, the experts at "AZ European". offer some tips about the most important component of the braking system - the brake pads.
There are two types of braking systems in cars - drum brakes and disc brakes. That disk brakes are superior in all criteria's is irrefutable, and so they are incomparably widespread. The disc brakes work in the same way as a handbrake does for a bicycle - the only difference being that the bicycle brake pads are scouring against the wheel itself, whereas a car has brake discs installed.
How do brakes work?
Brakes are used for deceleration - by pressing the brake pedal, the piston in the main brake cylinder pumps brake fluid through a set of pipes and into the brake system for each wheel. There, one or more pistons in the brake cylinder (more commonly known within the automotive industry as a ‘caliper’) begin to push the brake pads, until they come into contact with the brake discs. As a result of the brake pads rubbing against the wheels, the vehicle will slow down and eventually come to a halt. During this process, the front wheels need to do approximately 70% of the entire braking process, that is why the front brakes are generally required to be sturdier than the rear brakes. Therefore, the technical condition of the front brakes is particularly important.
The whole braking process should remain both simple and safe, so long as the brake pads are in working order and not only perform their purpose well, but also rub against the discs without damaging them. However, if the pads are worn out, they can press against the wheel discs with differing forces, the result of which is almost guaranteed to be tragic. Therefore the condition of the brake pads must not be neglected, and they must be changed when brake pad wear is visible. Timely replacement of brake pads will cost a lot less than a more thorough repair of the brake disc, and possibly even the replacement of other elements of the braking system. So, step by step.
There is no one ideal brake pad - everyone has to choose their own
There is no one-stop universal brake pad for each car and every driver. In addition to the fact that, much like other car parts, the brake pads are divided into two large groups - original and alternative, the brake pads also differ widely in their types and materials. The brake pads consist of a base plate and a brake pad, in which more than ten components may be used. There are four main types: semi-metallic, low-metal, organic and ceramic brake pads. Different brake pads are suitable for different types of cars and driving styles.
Semi-metallic brake pads consist of at least 65% metal. The remaining 35% is a mixture of carbon and other inorganic materials. The advantage of these types of pads is the ability to efficiently transfer heat, but the drawback is an excessive hardness which causes premature deterioration of the brake discs. However, semi-metallic brake pads are the best choice for sporty style drivers.
Low-metal brake pads are made mostly of organic materials, with the remainder consisting of no more than 30% metals. They have good thermal conductivity and provide efficient braking, but cost almost twice as much as semi-metallic brake pads.
Organic The basic material for organic brake pads is Kevlar, glass and carbon, while the metal component makes up no more than 15%. They are soft and quiet, but are more wearable than other types of pads, so they are not suitable for sporty or aggressive drivers. Organic brake pads are relatively cheaper and are often installed by car manufacturers.
Ceramic brake pads include ceramic fibers, synthetic rubber and non-ferrous metals. Such pads provide a stable friction coefficient and are less abrasive. Ceramic brake pads provide "sharper" braking than organic pads. Compared to metal-based brake pads, ceramic and organic pads are quieter. In Europe, where governments are increasingly fighting against various forms of contamination - including noise pollution, this is not an insignificant factor. However, the fact is that when compared to other types of brake pads, ceramic pads are usually the most expensive.
How to choose the most suitable brake pads for you and your car?
When choosing brake pads, car owners must take into account not only their driving styles and the power of their machine (the stronger the car, the more efficient the brakes need to be) but also the driving conditions most commonly faced - be it city driving with many intersections or long distance driving along motorways. Particularly important is the compatibility of the brake pads materials with those of the brake discs. It is often recommended to select the same type of brake pads installed by the manufacturer, which will be compatible with your cars brake discs. If this is not possible, attention must be paid to ensure that the disc and brake pad materials are compatible. Otherwise, one of two problems may arise. The brake pad material will not cause sufficient friction when coming into contact with the discs due, resulting in a weak braking process. Or, a situation can occur where the overly-rigid material of the brake pads do not wear, but instead wear out the brake discs. In order to prevent such problems, it is preferable to choose both brake pads and discs from one reliable manufacturer with a good reputation. If you do not have the confidence in your knowledge of your cars braking system, it is best to rely on the advice given by a reputable workshop.
How often should brake pads be changed?
It is inevitable that every time the brake pedal is pressed, the cars brake pads are eroding slightly and wearing out. Just as the durability of materials and driving style differ, the distance travelled between changing the pads is different also - there is no universal range of kilometers travelled or time period after which the brake pads should be changed. However, a thickness of 3mm can be used as a quick reference point - if the pads are worn out more than 3mm, the brakes are no longer considered to be safe. Not only this, but the brake pads may also begin to cause damage to the brake discs. Most vehicles are equipped with a brake pad deterioration indicator, which, when reaching critical wear-out level, will show a warning signal on the car dashboard. In addition, the degree of wear to the brake pads can be measured via the space in the wheel construction. When car maintenance is carried out by a trusted workshop, the car owner can rest assured that the braking system elements will be at least visually assessed and, if necessary, the workshop will also report the need to change parts of the braking system. If the owner of a car is not totally sure about the competence of their car mechanic, it is recommended to ask attention be paid to the brakes when visiting the workshop.
Important brake signals to be heard
The brakes are one of those car elements which report its wear and tear with very characteristic signals, which will urge even a driver with poor technical knowledge to visit a workshop. One of these signals is an unpleasant squeaky and scratchy sound, that can be heard during braking. If the brake pads are too worn, a small metal component, called an indicator, will produce an unpleasant sound whenever the brakes are pressed. When the indicator begins to squeak, the car owner still has sufficient time to drive to the workshop and have the brakes checked. However, it should be assumed that ignoring this unpleasant noise will result in the complete erosion of the brake pads, which will result in metal grinding against metal during braking, causing additional damage and a much higher cost of repair.
Another characteristic signal indicating problems with the braking system is the deviation of the car to one side or the other after pressing the brake pedal. The cause of this problem may be a stuck brake caliper. It may also occur when one brake pad on an axle iis completely worn out, but not the other, resulting in only one wheel braking accordingly. This situation can lead to a sudden "throw" of a car, and a tragic accident. So, if you notice similar symptoms you should be cautious, try to slow down and look seek a workshop immediately, where it will be possible to investigate the situation and diagnose the problem. It is due to the danger of this situation that the technical examination pays close attention to the equivalence of brake pads on both axles, with less attention paid to the ‘sharpness’ of the brakes.
Damage to the braking system is also indicated by the loss of resistance whilst pressing the brake pedal. If the brake pedal is easily pushed down to the floor without the car reacting accordingly, there is reason to suspect that there is a leak in the main brake cylinder or brake system. In this situation the car owner must first check the brake fluid level, and the seek help at a workshop. Alternatively, if pushing the brake pedal results in vibrations or pulsations, it is likely that the car has a twisted brake disc. Though not an immediate problem, the safety of both passengers and other road users must be taken into account and the car should be serviced as soon as possible. Vibrations in the steering wheel when the brake pedal is pressed between 90-100 km/h is also an indication of damage to the brake system.
Factors that “kills” brakes faster
Brake pads and other elements of the braking system will have to be replaced more frequently by sporty or aggressive drivers. Continuous aggressive/sporty driving adds an extra load to the brakes, and therefore also results in faster wear and tear. The lifetime of the brake pads does not gain from emergency situations when rapid braking is required at high speeds. A big additional load on brakes also results from driving in hilly areas with long and continuous braking. The biggest risk in the mountains is overheating of the brake system, which can literally boil the brake fluid and stop the brakes from working. Another risk that can be encountered in the event of the brakes overheating is a glazing of the brake pads surface. As a result of this, the material on the brake pads becomes so hard that friction between the pads and discs is no longer possible.
Other factors such as braking when towing a heavy trailer, long periods of towing and, of course, driving on the racetrack causes an additional load on the brakes. Therefore, it is recommended for drivers to check the condition of their vehicles when considering a trip to the mountains, a racetrack or similar high-risk conditions, so that they are not let down at the most crucial moments.
How the lifespan of brake pads can be extended
It is possible to extend the life of the brake pads, as well as other components in the braking system whilst driving, and furthermore increase fuel economy. One of the safest ways to achieve this is to lift off the accelerator pedal and decelerate using engine resistance. It may slow the car without the need to use the brake pedal. A similar effect can be achieved when driving smoothly and avoiding intense braking. In this case it is essential to keep in mind the need to keep a safe distance between the car in front and behind, so that such sensible braking does not end with a bad collision.
brake-pads-size
An essential parameter indicating the need to change the brake pads is the pad thickness. The thickness of a new brake pad is usually around 1.5 cm, which gradually decreases with continuous friction. When the pads reach a thickness of around 3 mm, it's time to change them.
brake-pads-visual-check
The brake pad and brake disc condition can also be visually inspected through the space in the wheel construction.
brake-disk-and-brake-pads
When car maintenance is carried out by a trusted workshop, the car owner can rest assured that the braking system elements will be at least visually assessed and, if necessary, the workshop will also report the need to change parts of the braking system. If the owner of a car is not totally sure about the competence of their car mechanic, it is recommended to ask attention be paid to the brakes when visiting the workshop.
new-brake-pads
There is no one-stop universal brake pad for each car and every driver. There are four main types of pads: semi-metallic, low-metal, organic and ceramic. Different brake pads are suitable for different types of cars and differ according to a drivers driving style. Therefore a choice must be made in an informed and responsible manner.
Check out our range of ATE, ATE Ceramic, Brembo, TRW, Ferodo, Valeo, Bosch, Remsa, Remsa Cermaic, Bendix + much more pads today!