What is the Brake Drum all about?
A brake drum is a smooth metal cylindrical housing attached to the rear wheel hub. It is an essential component of your car’s braking system that enables you to slow down or stop.
Most new cars (1999 and above) come with rotors at each wheel. Older cars may have drums at the rear wheels instead of rotors. It is the friction between brake shoes and drums that cause your car to slow down and stop.
As the drums wear out (get warped or grooved), they are unable to dissipate the heat caused by the braking system. This will cause the brake fluid to boil and weaken its ability to slow and stop the car.
Keep in mind:
- Your brake drums will become smaller as they wear out, and their size will determine if they need replacing.
- Defective brake drums sometimes cause damage to brake shoes.
- Brake drums cannot be repaired, only replaced.
- Both brake drums should be replaced at the same time, even if only one is damaged.
How it's done:
- Measure the thickness of brake drums.
- Remove and replace brake drums and shoes if the thickness is lower than specifications.
- Inspect wheel cylinder, springs, clips, and adjustment parts in the brakes.
- Lubricate backing plate.
- Perform road system to check brake system performance.
If you notice a clear fluid underneath your car or on the wheels, get it inspected as soon as possible. Do not drive the car with brake fluid leaking. It can make the brakes weaker and eventually lead to brake failure.
What common symptoms indicate you may need to replace the Brake Drum?
- Back of the car shakes when you brake.
- Car may pull left or right when you brake.
- Hand brake does not hold.
- Noise from rear brakes.
How important is this service?
When you apply your brake pedal, the brake drums rub against the brake shoes, creating friction that slows down your vehicle. If the brake drums are damaged, this friction is sporadic and inefficient, and your car will not brake as effectively. If the brake drums are worn down, they won’t be thick enough to dissipate the braking system’s heat, and the brake fluid will absorb the heat and reach a boiling point. Boiling brake fluid is less effective, and will lower the effectiveness of your brake system.