Vehicle Part - Brake Drums: Its Function, Safety & Depreciation

Vehicle Part - Brake Drums: Its Function, Safety & Depreciation


Brake drums are an essential component of drum brakes. Together with the brake shoe, a brake drum creates a friction couple that stops the wheel from turning. Another task of the brake drums is to absorb and discharge the heat generated during braking. This is very important because the frictional effect between the brake drum and the brake shoe lining decreases as the temperature increases. This is known as fading and can lead to the weakening of the braking effect at high temperatures.

The brake drum must be dimensioned sufficiently evenly to ensure an excellent braking effect regardless of the load. Its diameter should not be beyond the permissible limit under load and at high temperatures. Optimum surface hardness, good thermal conductivity, narrow form of the friction surface, and positional tolerances also guarantee stable friction values ​​and reliable and safe braking.

Brake drums are constantly exposed to water and road dirt, and road salt (in winter). Many well-known suppliers use brake drums with anti-rust coating in their product portfolio to prevent them from rusting too quickly. Anti-rust coatings will make sure that the brake drums continue to look well after replacement.

Many vehicle models feature integrated wheel bearings within the brake drums. For safety, you should replace the wheel bearing at the same time as the brake drum. For this reason, most manufacturers offer brake drums with integrated wheel bearings. These complete kits speed up service repair work, reducing repair costs.


The brake drum is essential in vehicle safety. It has relatively low wear and long service life. However, if the wear limit is exceeded (the inside diameter has become more significant than the permissible limit) or if damage occurs (for example, to the wheel bearing), reliable braking is no longer possible. If this happens, the brake drum must be replaced. To avoid significant differences in braking force within the vehicle axle, the brake drum should always be replaced with the axle whenever the axle is replaced.

If the driver senses a reduction in the braking effect of the drum brake, the vehicle should be taken to a specialist workshop immediately. Only trained professionals are authorized to install brake drums. You must follow the manufacturer's installation instructions.


Like all drum brake systems, the brake drum requires no maintenance by the driver. During regular service and maintenance, a qualified workshop checks the drum brakes for wear and effectiveness. If the brake drums or other parts of the brake drums need to be replaced, only high-quality components should be used. It must also be installed correctly. These two aspects are fundamental to braking performance and help the vehicle retain its value.