How to change brake pads? - disc and drum brakes

Brake pads, like brake discs and drums, tend to wear out over time. You can guess why this happens if you understand the structure of the car’s brake system: when you press the brake pedal, the pads are pressed against the disk or drum with force, blocking the rotation of the wheels. The system is very simple and effective, but it requires constant diagnostics and monitoring, otherwise you can get a lot of unpleasant surprises:

vibration of the brake pedal, it will have to be pressed with more force;
increased braking distance;
uneven tire wear;
complete brake failure.

To prevent all this from happening to your car, you need to replace the brake pads on time. It is difficult to say exactly after what period of time or after overcoming how many kilometers this operation needs to be carried out - pads from different manufacturers can withstand from 10 thousand to 100 thousand kilometers, your individual driving style must also be taken into account.

Disc Brakes

At the moment, almost all passenger cars have disc brakes on the front, and many on the rear, axles. Their device can be schematically described as follows:

a brake disc that is screwed to the hub and rotates with the wheel, the discs are usually ventilated - with perforations, internal channels and notches for better contact with the pads;
caliper - a metal case, consisting of two halves, it is attached to the suspension and is in a fixed position relative to the rotating disk;
brake pads - located inside the caliper and tightly clamp the disc after pressing the brake pedal;
working brake cylinder - sets the pads in motion with the help of a movable piston.

You can check the device of the brake system on the example of your own car. You will be able to see that there is a brake hose attached to the brake cylinder, and there may be brake pad wear sensors inside the caliper, and some models may have two brake cylinders per caliper.

Now, in order to replace the brake pads, you will have to follow this sequence of steps. First you need to get to the pads themselves, and for this you will need to remove the wheel. Then we will see the disk itself and the caliper attached to the side. The caliper may consist of several sections, or it may only consist of the upper section (bracket) and the section where the pads are fixed.

How to change brake pads? - disc and drum brakes

If done incorrectly, the caliper can break when it is under pressure. Therefore, it is necessary to use a screwdriver to separate the brake pads to the sides and bring the brake cylinder rod to the non-working position. Then the guide bolts for fastening the bracket are unscrewed and it is removed, now we can assess the condition of the brake pads.

If the pads are worn evenly, then this is a good sign - everything is fine, but if one of them is worn out more than the other, this may indicate that you need to check the condition of the brake disc itself, because it also wears out over time.

In addition, if your caliper is installed on special guides and can move in a horizontal plane, then you need to replace the anthers of the guide bushings, and lubricate the guides themselves with special grease or ordinary lithol.

Well, then you just need to put new pads instead of new ones and tighten everything as it was. Be very careful with the brake hose so that it does not kink or crack. You will also have to think about how to compress the brake cylinder piston, because it interferes with the installation of friction linings, you can use a gas wrench, clamp or hammer, it’s good if there is an assistant nearby.

After installing the wheel back, you need to bleed the brakes - press the pedal repeatedly to eliminate any gaps between the pads. In addition, experts advise checking the quality of the work performed and new pads by braking while driving, this will help you make sure everything is done properly.

How to change brake pads? - disc and drum brakes

Drum brakes

Drum brakes are arranged a little differently - 2 brake linings repeat the round shape of the drum and are pressed against its inner part, the working brake cylinder is responsible for their movement.

That is, to replace the pads, we will need to remove the wheel and brake drum. It is sometimes impossible to remove it and you have to loosen the parking brake adjustment nut.

Having removed the drum, we can see the brake shoes, they are attached to the drum with fixing springs, and are connected to each other by coupling springs. It is enough just to bend the spring clip with pliers. It is also necessary to disconnect the special hook that connects the block to the tip of the handbrake cable. Between the pads there is also a spacer spring. The installation process is carried out in reverse order.

Do not forget to check the condition of the brake disc and working brake cylinders during the replacement of pads. Your safety will depend on this.

Video showing how to change the front pads on VAZ cars