Brake Drum Replacement: What You Need to Know

Brake Drum Replacement: Step-by-Step Process

Before you plan to attempt a DIY brake repair, understand that your car’s brakes are a critical safety system that requires precise, skillful handling. That’s why it’s best to let a qualified professional handle the repairs, since even a small mistake can affect performance or, in serious cases, lead to brake failure.

Here’s how a mechanic will proceed:

1. Park on a flat surface and place wheel chocks to prevent the vehicle from moving.

   NOTE: Avoid engaging the parking brake lever, as it can lock the rear wheel, making it difficult to remove the brake drums. Drum brakes are most commonly found on the rear axle of many vehicles.

2. Use a jack to raise the vehicle and place it securely on a jack stand.

3. Remove the wheel by loosening the lug nuts to access the drum brake assembly.

4. Inspect the brake drum for wear, damage, or excessive grooving that could affect braking performance.

5. Disassemble the brake components by removing the return spring, hold-down pins, and adjuster mechanism. The mechanic may use a special tool, such as a set of needle-nose pliers, for precision.

6. Remove the retaining clip and any remaining screw securing components, keeping track of each part’s position.

7. Remove the brake shoes from the assembly.

8. Evaluate each brake shoe for wear, cracks, or thinning, and replace it with a new shoe if any damage is visible.

9. Inspect the wheel cylinder for leaks, corrosion, or stuck pistons, and check for any brake fluid leaks around the rubber boots. They’ll replace the wheel cylinder if it’s faulty.

10. Clean the brake drum, backing plate, and surrounding components using a brake cleaner to remove dust and debris.

11. Check all hardware, including springs or clips, and replace any damaged parts.

12. Reinstall the brake shoes onto the backing plate, ensuring proper alignment with the adjuster mechanism.

13. Reconnect the return spring and hold-down pins securely.

14. Install the new brake drum by sliding it onto the wheel hub and ensuring it fits properly over the brake shoes.

15. Reattach the wheel and tighten the lug nuts to the manufacturer’s specified torque.

16. Lower the vehicle safely from the jack stand.

17. Test the brakes with a short drive to confirm proper operation.

How Much Does a Brake Drum Replacement Cost?

A brake drum replacement typically costs around $380 to $840 per axle.

Brake drums are typically replaced per axle, meaning both wheels on the same axle are serviced together. This is done to ensure balanced braking performance, as uneven wear between sides can lead to pulling, reduced stability, and inconsistent stopping power.

Here’s the cost breakdown:

• Parts cost (per wheel): $100 to $250
• Labor cost (per wheel): $90 to $170
  

The expenses will be higher if you have to replace the brake shoes too. A new shoe (parts only) typically costs around $120 to $160.

Why is It Important to Replace a Worn Brake Drum?

Replacing damaged brake drums is important because they ensure consistent and effective braking performance. Worn or uneven drums can cause pulling, longer stopping distances, and reduced vehicle control.

Timely brake repair prevents damage to other components in both disc brakes and drum brake systems.

NOTE: Many vehicles use drum brakes at the rear and disc brakes at the front. If you’re fixing worn rear drum brakes, it’s a good idea to check the front brake pads and rotors for wear to ensure balanced performance.

5 Warning Signs that You Need a Brake Drum Replacement

You may notice the following symptoms if your brake drums are worn:

1. Scraping noises: A worn brake shoe may expose the metal backing, which rubs against the drum, causing a harsh noise when braking.

2. A low brake pedal: If your brake pedal feels unusually low, it may indicate an excessive gap between the brake shoes and drum, often caused by wear or improper adjustment. However, this can also point to other issues, such as a brake fluid leak or a master cylinder problem.

3. Pedal pulsation: If the brake drum becomes uneven, it may not make consistent contact with the brake shoes, resulting in a pulsating brake pedal. This unevenness can develop over time due to heat, wear, or repeated heavy braking.

4. Loose parking brake: If your parking brake lever feels loose or stays engaged, it may indicate worn brake drums or a sticking parking brake cable. Since the emergency brake system relies on drum friction, reduced effectiveness is a clear sign that something might be wrong.

5. A soft or spongy pedal: Although rare, a damaged drum can contribute to a soft pedal. More commonly, this issue is caused by air in the brake lines, which requires proper bleeding of the braking system.

How Long Do Brake Drums Last?

Drum brakes, as a complete assembly, typically last between 150,000 and 200,000 miles, while brake shoes usually need replacement every 30,000 to 40,000 miles.

On the other hand, disc brake components like brake pads last around 30,000 to 70,000 miles, while brake rotors last 50,000 to 80,000 miles.

However, these estimates can vary based on real-world conditions. Driving habits (such as frequent braking or carrying heavy loads), road conditions, climate, and overall maintenance all play a role in how long brake components last.

In vehicles that regularly carry heavy loads, such as trucks and other commercial vehicles, brake components may wear out more quickly due to increased strain.

The rear drum brakes in your vehicle will probably last longer than the front disc brake components. This difference isn’t due to the brake design itself (drum vs disc), but because of how braking force is distributed. The front brakes handle most of the load, especially as weight shifts forward during braking, which wears them out faster than the rear brakes.

7 Essential Brake Drum Maintenance Tips

Follow these practical steps to keep your brake drums in top condition:

1. Have a mechanic check for scratches, cracks, or corrosion on brake drums to catch issues early.

2. Change worn components of your drum brake assembly as needed using high-quality replacement parts for enhanced safety.

3. Use a dedicated brake cleaner to remove dust and debris that can interfere with proper friction and reduce braking efficiency. Do not clean brake components with water, as it can cause rust and corrosion.

4. Apply appropriate brake lubricant to the drum brake contact points to ensure smooth operation and prevent seizing.

5. Replace brake fluid every 2 years or 30,000 miles to maintain proper hydraulic pressure and braking performance.

6. Avoid aggressive braking to prevent overheating and excessive wear.

7. Do not exceed the vehicle’s weight limits, as extra load increases strain on the braking system.