Rear brake disc replacement and repair

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Brake discs are the most important part in the system of any car. The condition of this part depends on the safety of the driver, passengers and other road users. If one of the discs is worn out, this is a direct safety hazard on the road. Often the front discs experience higher loads, but this does not mean that the rear brake disc is not a critical part. This element requires maintenance, replacement and repair in the same way as the front.

What affects wear?

There are no clear parameters on the issue of wear. Each manufacturer gives its own characteristics and digital parameters regarding this. There are tables for various makes and models of cars, as well as numerical data for each model within the same brand. Various indicators are related to the power of the engine, the weight of the car, as well as the consequences of all the physical forces acting on the car inbraking process.

Materials

First of all, the wear rate is affected by the materials from which the rear brake disc is made. The latter is usually made of cast iron, but today these elements are made from high-tech carbon and ceramic materials.

Mechanical factor

The resource is significantly affected by the mileage of the car, as well as the brake pads. If poor quality pads are installed, wear will be uneven. Also, scratches will subsequently form on the surface of the part. In this case, replacing the rear brake discs will help out. Sometimes you can repair parts by turning. In this case, it is recommended to replace the pads.

Vehicle operation

This is a factor that mostly depends on the driver. For example, in winter, while using the car, it is very easy to deform the rear brake disc. In the process of movement, it heats up, and since it is quite cold outside, the metal is deformed from serious temperature changes. If this happens often enough, repair or replacement is inevitable.

Riding style

Manufacturers present specific figures. So, the rear brake disc of an average driver should work for 100-150 thousand km. However, some drive in such a way that after 15 thousand it is necessary to carry out restoration - the disk is worn out by more than half due to an aggressive driving style. If emergency braking is performed, this is a direct road to a speedywear.

How to Diagnose

There are some machine codes that may indicate whether rear brake discs need to be replaced or not. Pay special attention to these symptoms, because safety depends on them.

The first thing to tell about wear is the locking of the rear brakes when you press the brake pedal. Also, the failure of the brake disc can be recognized by the characteristic rattle when you press the pedal. In addition, during the braking process, vibrations, jerks and other sounds that were not there before may occur. You can also see the degree of wear visually - chips, cracks, and bumpers are visible on worn brake discs. It is quite possible to carry out diagnostics with your own hands using a measuring tool. For example, rear brake discs (including Megan 2nd generation) have a nominal thickness of 8 mm. As for the minimum indicator, the manufacturer claims that it is 7 mm.

You can carry out diagnostics right in the garage, but first you need to dismantle the wheels. Next, a replacement, repair, or a trip to the service station is carried out. If the rear brake disc has a defect such as uneven thickness, then a groove can be made to restore it in this way. If surface destruction is observed, only the replacement of the component in question will save.

Restore or replace?

When you can determine the degree of wear (or if you notice that the brake pedal twitches whenbraking), the car owner is faced with the following question: replace the damaged part or try to restore it? Many are trying to implement the second option. It must be remembered that it is possible to grind a disc, but only if the residual thickness is four or more millimeters.

Specialists of service centers recommend changing the rear brake discs ("Ford" is no exception). However, if the price of a new part seems too high, you can try to repair it yourself.

It is important not to forget that the larger the layer of metal removed during the repair, the shorter the service life of the described part will be. Also, experts do not recommend installing contract discs. In this case, you will not have exact data on where they were installed, how they were used, and the like. They may also need to be repaired soon.

How brake discs are restored

There are no difficulties with the repair of the front elements - they are machined without removing them from the car (if it is front-wheel drive). Start the engine and use a special tool to process the working surface of the part. If you have special equipment, you can also machine the rear brake disc of the Kia Sorento. The rear wheel is removed, then the car is raised on a jack. Further, the device is fixed through the fixture to the wheel bolt and sets the disk to rotate. With the help of another device that is attached to the caliper, the groove itself is performed.

You can also perform this procedure on a lathe. But then you have to remove the disk and carry it to the turner. As a result, we get the most even and smooth surface. However, after mounting the disc on the vehicle, wobble may occur.

What is needed to replace the rear brake elements

So, if repair is not possible or the wear is too great, a replacement is made. To do this, you must purchase original products. It is important that when replacing two discs on the rear axle at once. It is also recommended to install new pads. Ideally, if the discs and pads are from the same brand. Some car owners, with a desire to save money, do not change the pads for new ones by replacing the discs. This will further lead to rapid wear of the element and the appearance of grooves on it.

Replace Tool

You'll need a few tools to get the job done. This is a standard set of keys and heads, a jack, a wheel wrench. A pit or overpass, a tripod for fixing the car, wheel chocks, and wire will not be superfluous.

It is best if this operation is performed with an assistant. This will greatly speed up the process of replacing the rear disc in the garage. Before you start dismantling, you should find out if you need self-locking bolts, or you can do with ordinary ones.

How to replace a brake disc with your own hands

If we exclude some design features of various makes and models of cars, the technology for dismantling and replacing rear discs forall machines are the same.

Let's see how you can replace the Renault Megane rear brake discs yourself. The vehicle must be secured front and rear with wheel chocks. Next, jack up the back of the car. Before removing the disc, dismantle the operating point and press the piston on the working cylinder. The hub must be thoroughly cleaned of dirt. This action will allow you not to change the wheel bearing in the future (but if it was already buzzing, then an urgent replacement is needed). Next, you should invite an assistant - he must press the brake pedal, but you can also tighten the handbrake. Then unscrew the brake disc mounting bolts.

Next, the brake caliper is removed and fixed with a wire. This is done so that the hose on the brake system is not damaged. Then the caliper assembly is disassembled - the pads, springs and bracket are removed. The hub is fixed, the bolts are completely unscrewed and, finally, the disk is removed. To install a new one, you need to do all these operations in reverse order. The main thing is not to forget to install new pads. After replacement, be sure to bleed the brakes. Air in the system should not be. Otherwise, it is simply dangerous to use such a car.

Conclusion

We looked at how to repair or replace the rear brake disc with your own hands. This is not the most difficult operation performed when servicing a car. You need to be attentive to any details of the braking system, because safety on the road depends on it.