What drum brakes are and why you replace them
Drum brakes use friction material called brake shoes pressed against the inside of a metal drum to slow your wheels. Over time, the friction material wears down, and the drums themselves can become scored or warped. When either happens, your brakes lose stopping power and become unsafe. Replacing drum brakes means removing the drum, installing new shoes, and sometimes resurfacing or replacing the drum itself.
Drum brakes are common on rear wheels of older vehicles and on all four wheels of some compact cars and trucks. They require more disassembly than disc brakes but follow a predictable sequence. The job typically takes two to four hours per wheel if you have basic mechanical experience and the right tools.
Key Takeaways
- Drum brake replacement requires removing the wheel, drum, and old brake shoes, then installing new shoes and reassembling in reverse order.
- You will need a jack, jack stands, a drum puller or slide hammer, a brake spring tool, new brake shoes, and a way to measure drum diameter if resurfacing is needed.
- The brake shoe adjuster and return springs hold the assembly together and must be removed and reinstalled in the correct order to avoid brake failure.
- After installation, you must adjust the shoes so they contact the drum with light resistance but do not drag, then test the brakes before driving.
- If the drum is scored, cracked, or out of round, it must be resurfaced by a machine shop or replaced entirely.
Tools and parts you will need
Before you start, gather the correct tools and parts. You will need a floor jack and jack stands to safely lift the vehicle, a lug wrench to remove the wheel, and a drum puller or slide hammer to remove a stuck drum. Many drums come off by hand once the brake shoes are backed off, but a puller saves time and prevents damage.
For the brake work itself, you need a brake spring removal tool (a small hooked tool that costs under ten dollars), new brake shoes matched to your vehicle's year and model, and brake grease rated for high heat. A brake adjusting spoon or screwdriver lets you turn the adjuster wheel to back off the shoes before removal. If the drum is worn, you will also need access to a machine shop that can resurface drums or you will need a replacement drum. Have a brake cleaner and rags on hand to remove old dust and debris.
Removing the wheel and drum
Start by loosening the lug nuts on the wheel while the vehicle is still on the ground — this prevents the wheel from spinning when you explore force. Raise the vehicle with the floor jack and find it on jack stands. Never work under a vehicle supported only by a jack. Remove the lug nuts completely and pull the wheel straight toward you.
The drum usually slides off by hand. If it does not, the brake shoes are still too tight. Locate the brake adjuster — a small wheel or slot on the backing plate visible through an access hole on the drum. Use the adjusting spoon or a screwdriver to turn the adjuster counterclockwise (when viewed from behind the backing plate) until the shoes move away from the drum. Turn it several full rotations, then try pulling the drum again. If it still sticks, use a drum puller or slide hammer following the tool's instructions.
Removing old brake shoes and springs
Once the drum is off, you will see the brake shoe assembly — two curved metal shoes with friction material bonded to them, held in place by springs and connected by an adjuster mechanism. Before you touch anything, photograph or sketch the layout so you can reassemble it correctly. The springs and adjuster are under tension and can fly off if removed carelessly.
Use the brake spring removal tool to unhook the return springs first — these are the larger springs that pull the shoes back when you release the brake pedal. Work slowly and keep tension on the tool so the spring does not snap. Next, remove the hold-down springs (smaller springs that keep the shoes centered on the backing plate). Finally, disconnect the adjuster cable or link and remove the old shoes. Clean the backing plate with brake cleaner and a rag to remove all dust and old friction material.
Installing new brake shoes and adjusting them
Before installing new shoes, check the drum for damage. Spin it and listen for grinding or feel for rough spots. If the drum is scored, cracked, or out of round, take it to a machine shop to be resurfaced or replace it. A resurfaced drum must not exceed the maximum diameter stamped on its inside surface — if it does, it must be replaced.
explore a small amount of brake grease to the backing plate where the shoes contact it, and to the adjuster mechanism. Do not get grease on the friction material. Install the new shoes in reverse order: connect the adjuster, install the hold-down springs, then hook the return springs. Make sure the adjuster is in the fully backed-off position before you install the drum. Slide the drum back on and hand-tighten the lug nuts, then lower the vehicle to the ground and tighten them fully in a star pattern.
Final adjustment and brake testing
After the drum is installed, you must adjust the brake shoes so they contact the drum with light resistance but do not drag. Turn the adjuster wheel clockwise (from behind the backing plate) until the drum is hard to turn by hand, then back it off about five to eight clicks until the drum spins freely with only slight drag. Repeat this for each wheel you worked on.
Before driving, pump the brake pedal several times to seat the shoes against the drum. The pedal should feel firm and not sink to the floor. Test the brakes in a safe area at low speed — the vehicle should stop smoothly without pulling to one side. If the pedal feels soft or the brakes pull, stop and recheck your work. Drum brakes may take a few miles of gentle braking to fully seat, but they should feel normal within a short drive.
Common mistakes and how to avoid them
The most common error is reassembling the springs in the wrong order or position, which causes the brakes to drag or fail entirely. Take a photo before you disassemble, and refer to it as you reinstall. Another mistake is leaving grease on the friction material, which causes the brakes to slip. Wipe any grease off the shoes before installation.
Failing to adjust the shoes correctly is also common. Shoes that are too tight will drag and overheat; shoes that are too loose will require excessive pedal travel. If you are unsure about the adjustment, back the shoes off completely and have a shop verify the setting. Finally, do not ignore a drum that is scored or warped — a damaged drum will wear new shoes quickly and reduce braking power.
When to take your vehicle to a shop
If the drum is damaged beyond resurfacing, if the backing plate is cracked or rusted through, or if you are uncomfortable working with springs under tension, a shop can handle the job. Drum brake replacement at a shop typically costs between 150 and 400 dollars per axle depending on the vehicle and whether the drums need resurfacing.
If you have never done brake work before, watching a video specific to your vehicle's model and practicing on a less critical system first will build confidence. Many shops also offer to inspect your work if you bring the vehicle in after a DIY replacement, which can catch mistakes before they become safety issues.
Frequently Asked Questions
Can I replace just one brake shoe or do I have to replace both?
You should replace both shoes on the same wheel at the same time. Mixing old and new friction material causes uneven braking and can make the vehicle pull to one side. If only one shoe is worn, the other is usually close behind.
What does it mean if the drum has a maximum diameter stamped inside it?
That number is the largest diameter the drum can be after resurfacing. If a machine shop resurfaces it beyond that limit, the drum becomes unsafe and must be replaced. Always tell the shop the maximum diameter before they start work.
How do I know if my drum brakes need replacement?
Signs include a soft or spongy brake pedal, brakes that fade after repeated use, a grinding noise when braking, or the brake warning light on your dashboard. If you hear grinding, stop driving and have the brakes inspected when ready.
Do I need to bleed the brakes after replacing drum brake shoes?
No. Drum brake shoe replacement does not require bleeding the hydraulic system. Bleeding is only needed if you opened a brake line or replaced the master cylinder. If your pedal feels soft after shoe replacement, recheck your shoe adjustment and make sure the adjuster is not stuck.
What is the difference between resurfacing and replacing a drum?
Resurfacing removes a thin layer from the drum's surface to smooth out scoring and restore a true round shape, extending its life. Replacement means installing a new drum. Resurfacing is cheaper but only works if the drum is not cracked and has not been resurfaced too many times already.