Brake drums: common defects and their signs

1. Wear out.
   • Efficiency of braking lowers.
   • The wheel may jam if component is critically worn.
   • Leaks of working liquid are seen with the naked eye.
   • Wheel vibration with strange noise is felt when braking.
   • Wheel axial runout appears.
   • The brake pedal vibrates when pressed.
2. Soiling.
   • The car randomly changes its trajectory when braking.
   • Screeching sounds are heard when pressing brake pedal.

How to repair or replace brake drums?

Brake drums surface wears out over time and grooves from brake shoes appear on it. It lowers efficiency of braking system work. In this case repair of brake drums can be performed, particularly their grinding. It consists in grinding down a thin layer from the brake drum surface with the help of special device, thus restoring structure of the surface. Such repair can be performed only in case brake drum wall thickness is within the acceptable limits and only at a service station because high-precision equipment and special skills are required for grinding.

If damages are significant or the component is worn out, then brake drum replacement is necessary. It is recommended to replace them in pairs on one axle. Algorithm of replacement is the following:

1. Provide vehicle immobility, unscrew the wheel connection bolts. Make sure that wheels are not fixed by the parking brake. Lift the car body with the help of a jack and demount the wheel.
2. Unscrew adjusting pins of the brake drum.
3. Remove the brake drum from the wheel hub with the help of a rubber hammer. Clean the mounting surface, apply graphite lubricant to the hub surface and install a new component.
4. Perform assembling in reverse order.

It is recommended to replace brake shoes together with brake drums and also install new hub bearings into the car.