Car brakes fall into two categories: drum brakes and disc brakes.
Ever wonder how they’re different?
In this article, we’ll start by comparing the drum brake system and the disc brake system and then cover their pros and cons. Later, we’ll answer five FAQs about drum brakes vs disc brakes to give you a clear understanding of each braking system.
This Article Contains:
- Drum Vs Disc Brakes: 3 Key Differences
- What Are The Pros And Cons Of Using The Drum Brake System?
- What Are The Pros And Cons Of Using Disc Brake System?
- 5 FAQs About Drum Vs Disc Brakes
Let’s get right to it.
Drum Vs Disc Brakes: 3 Key Differences
Although both the drum and disc braking systems slow down your moving vehicle by generating friction, there are some key differences between the two, like their:
A. Method Of Braking
Both drum brakes and disc brakes use hydraulic mechanisms to generate braking force.
In a drum braking system, this pressurized brake fluid forces the pistons inside the wheel cylinder outwards. These pistons, in turn, push a set of drum brake shoes against the brake drum to generate friction, slowing down your vehicle.
On the flip side, in a disc braking system, the pressurized brake fluid is delivered to a brake caliper. This brake caliper then squeezes a set of disc brake pads (a.k.a. friction pads) against the brake rotor (a.k.a. wheel rotor or brake disc), generating stopping friction.
B. Braking Power
Your rotating disc brakes are constantly exposed to the atmosphere, so they can dissipate the heat generated during braking quickly.
But since drum brakes are closed (not exposed to air), heat dissipation would be much slower. This can cause brake fade, which is a loss in braking power due to overheating due to inefficient heat dissipation.
The disc brakes’ exposure to the air outside also means that it’ll work better in wet conditions.
Since a disc brake is open to the atmosphere, it can sling off any moisture accumulated while driving quickly. Moreover, the brake or friction pads rubbing against the wheels can also wipe away any water, just like how your wiper blade wipes the water off your windshield.
In drum brakes, however, moisture might get trapped inside the drum and take more time to dry. This can affect the frictional force your brake shoe and brake drum pair can generate, compromising braking power.
C. Brake Maintenance Needs
Disc brakes are self-cleaning.
Remember, your brake pad wipes the rotor when engaged. This usually removes any debris that may be clinging to the wheel or brake rotor.
On the other hand, since drum brakes are generally closed, they’re prone to accumulating the brake dust generated by the drum brake shoes. If the dust accumulated becomes excessive, your brake performance may decline.
As a result, your drum brakes will need to be cleaned and serviced more often than disc brakes to ensure optimum brake performance. Additionally, since your drum brakes include more components, they’re usually more difficult to service.
Now that you know the critical differences between drum brakes and disc brakes let’s move on to the pros and cons of each of these brakes.
What Are The Pros And Cons Of Using The Drum Brake System?
Let’s first check out the advantages of using drum brakes for your vehicle.
Usually, drum brakes:
- Require less hydraulic pressure due to a built-in self-energizing effect
- Are somewhat easy to recondition
- Are affordable to manufacture and install
Unfortunately, drum brakes have a few significant disadvantages as well.
- Can overheat easily and cause drum distortion, which in turn leads to vibrations while braking
- Involve several parts, which leads to more chances of failure
- Take more time to service due to their complexity
Next, let’s take a glimpse at the upsides and downsides of using disc brakes in your vehicle.
What Are The Pros And Cons Of Using The Disc Brake System?
Disc brakes are a fantastic addition to your car because they:
- Offer excellent stopping power
- Are less susceptible to rusting and degradation
- Experience less brake fade, leading to more consistent disc braking force
However, these brakes have their own set of limitations.
- Are costlier to manufacture and install
- Are difficult to recondition
- Require a separate parking brake (a.k.a. handbrake or emergency brake) mechanism
Still confused about drum vs disc brakes?
We’ll discuss the answers to the most commonly asked questions related to drum vs disc brakes now.
5 FAQs About Drum Vs Disc Brakes
Here are answers to five questions car owners frequently ask about drum brakes and disc brakes:
1. What Are The Critical Components In Drum Brakes?
A drum brake system has the following five key components:
- Brake drum: a large metal drum that rotates with your wheel and forms a frictional pair with your drum brake shoes.
- Brake shoe: a curved metallic block coated with friction material (a.k.a. brake lining) that rubs against the brake drum to generate stopping friction.
- Wheel cylinder: a cylindrical brake component with pistons inside that pushes the drum brake shoes outward as pressurized brake fluid is forced into it.
- Return or retracting spring: a steel spring that pulls the drum brake shoes away from your brake drum as soon as you release the pressure on your brake pedal.
- Self-adjuster: a small brake lever that maintains the gap between the brake shoe and drum to ensure that they stay close enough when brakes aren’t applied but don’t touch each other.
2. What Are The Critical Components In Disc Brakes?
Disc brakes have three main components, and they are:
- Brake rotor: an iron, steel, ceramic, or carbon-ceramic rotating disc connected to your vehicle’s axle that turns along with the wheel.
- Brake pad: a metallic piece coated with friction material or brake lining that generates stopping friction along with your brake disc or rotor.
- Brake caliper: metallic housing that houses your disc brake pads and pushes them against the wheel or brake rotor when the brake pedal is pressed down.
3. How Do I Know Which Brake System My Vehicle Uses?
Most modern cars have disc brakes for the front wheels.
As for the rear wheel set, you’ll either find drum or disc brakes. In lots of cars, drum brakes may be more common for the rear axle since they’re less expensive.
Why use disc brakes for the front wheels?
Usually, while braking, the weight of the car shifts forward. This means that you’ll need more stopping power in the front wheels. And since a disk braking system offers more stopping power, fitting disc brakes at the front is recommended.
In case you want to check which category your vehicle’s front or rear brakes belong to, you can try taking a peek through the wheels:
- For drum brakes, you’ll come across a large cylindrical drum that’s almost touching the inside of your vehicle’s wheel.
- And for disc brakes, you’ll see a flat rotor with a wider component (brake caliper) at the front or rear of your rotor.
4. What Are The Most Common Symptoms Of Failing Brakes?
Whether your vehicle uses a drum brake assembly or a disk brake assembly, it’s crucial to keep track of its condition to stay safe on the road.
If you notice any of these symptoms, it could be an indication that your drum or disc brakes are malfunctioning:
- The brake warning light gets activated
- Your brake pedal feels spongy or sinks to the floor
- There’s brake fluid leaking from your brake drum or caliper
- You experience inconsistent braking power while driving
- You hear grinding, rumbling, or squealing noises when you hit the brakes
- The brake lights on your vehicle won’t turn OFF
5. What To Do When Your Drum Or Disc Brakes Fail?
If you notice any issues with your vehicle’s brake system, take your car to a repair shop or request a mobile mechanic to come over to your driveway ASAP.
We recommend asking a professional car technician to come over to your driveway since driving around with defective brakes can be a safety hazard.
However, when hiring a mechanic, ensure that they:
- Are ASE-certified
- Offer a service warranty
- Use only high-quality replacement parts
But where can you find such a mechanic?
Just use RepairSmith — a convenient and accessible mobile auto repair solution.
- You can book all your repairs online
- You are guaranteed upfront and competitive prices
- Our ASE-certified technicians come to your driveway to repair or service your vehicle
- Only state-of-the-art equipment and high-quality replacement parts are used to repair or service your vehicle
- You get a 12,000-mile | 12-month service warranty on all vehicle repairs
Disc brakes are more effective than drum brakes and are more durable, making them the preferred choice for newer vehicles.
However, this doesn’t mean that drum brakes are going away anytime soon. Their lower costs and the possibility for reconditioning make the rear drum brake a viable option for most car owners.
However, irrespective of the type of brakes you may use, you need to keep them in check.
Fortunately, you can turn to RepairSmith for this.
Just book your repairs online, and our certified technicians will come to your driveway to take care of everything!