Replacing Rear Brake Shoes & Adjuster Strut

Maintaining your vehicle's braking system is paramount for your safety and the safety of others on the road. While disc brakes are prevalent on the front axle of most modern cars, many vehicles still rely on drum brakes for the rear, often integrated with the handbrake mechanism. Within these drum brake systems, the brake shoes and the often-overlooked adjuster strut play a crucial role in ensuring effective and balanced braking. Over time, these components wear down, leading to reduced braking efficiency, uneven stopping, or even a complete loss of rear braking. This guide will walk you through the process of replacing your rear brake shoes, including the adjuster strut, providing you with the confidence to tackle this essential maintenance task yourself and restore your vehicle's optimal stopping power.

Before you begin, remember that working on your car requires patience and a strict adherence to safety protocols. If you're unsure at any point, it's always best to consult a professional mechanic. However, with the right tools and a careful approach, replacing your rear brake shoes is a rewarding DIY project that can save you a significant amount on labour costs.

Essential Tools You'll Need

Gathering all the necessary tools before you start will make the job much smoother and prevent unnecessary interruptions. Here's what you'll need:

• A Pair of Pliers: Indispensable for bending and pulling split pins, as well as manipulating various springs within the brake drum assembly.
• 17mm and 24mm Sockets: The 17mm socket will typically be for your wheel bolts, while the 24mm (or similar large size) will be crucial for the main hub nut, which secures the brake drum and wheel bearing. Ensure you have a sturdy ratchet or a breaker bar for these.
• Jack and Axle Stands: Absolutely non-negotiable for safety. A reliable hydraulic jack will lift the car, but axle stands are what truly support the vehicle while you work, preventing it from falling. Never work under a car supported only by a jack.
• Wheel Brace or Breaker Bar: For loosening those often-stubborn wheel bolts. A breaker bar provides extra leverage.
• Flat-Headed Screwdriver: Useful for prying off dust covers, and potentially for assisting with stubborn springs or components.
• Wire Brush: For cleaning rust and debris from the backplate and other components.
• Brake Cleaner: Essential for cleaning new components and any grease or dirt from the drum and backplate.
• Copper Grease or Anti-Seize Compound: For applying to contact points on the backplate to ensure smooth movement of the new shoes and to prevent seizing.
• New Split Pins: Always use new split pins when reassembling; they are a one-time use component.
• New Brake Shoes & Adjuster Strut Kit: Ensure you have the correct kit for your specific make and model. Often, the adjuster strut and springs are included.

Step-by-Step Guide to Replacing Your Rear Brake Shoes

Step 1: Prepare Your Vehicle and Ensure Safety

Begin by parking your car on a flat, level surface. Engage the handbrake and place chocks in front of the front wheels to prevent any movement. Using your wheel brace or breaker bar, slightly loosen all the wheel bolts on the rear wheel you intend to work on. Just a quarter turn should be enough to break them free. Now, position your jack under the appropriate jacking point on the vehicle's chassis, near the rear wheel. Raise the car until the wheel is clear of the ground. Immediately, place your axle stands securely under the car's frame, adjacent to the jacking point. Slowly lower the car onto the axle stands, ensuring it is stable before proceeding. Once the car is safely supported, you can fully remove the wheel bolts and carefully lift the wheel off the hub. Set it aside safely, ensuring it won't roll or fall.

Step 2: Accessing the Hub and Removing the Drum

With the wheel removed, you'll see the dust cover protecting the hub nut. Using your flat-headed screwdriver, carefully pry off this dust cover. It might be a snug fit, so take your time not to damage it. Once exposed, you'll see the large hub nut, secured by a split pin. Using your pliers, bend the ends of the split pin straight and then pull it out. Keep it safe, but remember you'll be using a new one for reassembly. Now, using your 24mm (or appropriate size) socket and a breaker bar, loosen the hub nut. Do not remove it completely just yet. With the nut loosened, you can now gently pull the brake drum outwards. If the drum is stubborn and feels stuck, it's often due to a lip of rust on the edge or the shoes being slightly adjusted. A few gentle taps with a rubber mallet around the drum's edge can help loosen it. If it still won't budge, try backing off the handbrake adjustment slightly from under the car, or carefully using a screwdriver through the wheel bolt holes to manipulate the adjuster strut. Once free, carefully remove the drum and the wheel bearing (which often comes out with the drum or stays on the spindle). Place them somewhere clean and safe.

Step 3: Dismantling the Old Brake Shoe Assembly

Now you'll have a clear view of the entire brake shoe assembly mounted on the backplate. Take a moment to observe how everything is connected – perhaps even take a photo for reference. Begin by unhooking the upper return spring, which spans across the top of the two brake shoes. Use your pliers to carefully unhook it. Next, you'll need to remove the spring cups, springs, and retainer pins that hold each brake shoe to the backplate. Using your pliers, depress the spring cup firmly against the spring and turn it 90 degrees. This will align the slot in the cup with the flat part of the retainer pin, allowing you to lift off the spring and the cup. Once these are removed, the retainer pin can be pulled out from the back of the backplate. Repeat this process for both brake shoes. With the springs and retainer pins removed, the brake shoes should now be relatively free. Carefully disengage the handbrake cable from the rear brake shoe. The adjuster strut and its associated lever and spring can now also be removed. Pay attention to how the adjuster strut was positioned, especially the longer, straight part of its fork.

Step 4: Inspecting the Backplate and Wheel Cylinder

With the old brake shoes removed, now is an excellent time to inspect the condition of the wheel cylinder and the backplate. Check the wheel cylinder for any signs of fluid leaks, which would appear as dampness or fluid around the rubber boots. If there are any leaks, the wheel cylinder will need to be replaced before reassembly. Use a wire brush to clean any rust, dirt, or old brake dust from the backplate, especially around the areas where the brake shoes make contact and slide. A clean surface will ensure the new shoes move freely and correctly. You can apply a very thin layer of copper grease or anti-seize compound to these contact points on the backplate, but be extremely careful not to get any on the brake drum or the new brake shoe friction material.

Step 5: Installing the New Brake Shoes

Take your new brake shoes out of their box and confirm they are identical to the old ones you removed. Begin by installing the front brake shoe. Attach the lower return spring to it, and then secure the shoe in position on the backplate using the new retainer pin, spring, and cup. Ensure the retainer pin is fully inserted from the back of the backplate, and the spring cup is correctly depressed and turned 90 degrees to lock it in place. Next, attach the handbrake cable to the rear brake shoe. This can sometimes be a bit fiddly, but it's crucial to do it before locating the shoe fully onto the backplate. Once the handbrake cable is engaged, carefully locate the rear brake shoe onto the backplate, again securing it with its retainer pin, spring, and cup.

Step 6: Refitting the Adjuster Strut, Lever, and Springs

This is a critical step for proper brake function. Refit the adjuster strut between the two new brake shoes. It is vital to note that the longer, straight part of the strut's fork must be positioned behind the rear brake shoe. If installed incorrectly, the self-adjusting mechanism will not work. Now, refit the adjuster lever and its spring, making sure that the spring is correctly seated in the front brake shoe and that the lever engages with the adjuster strut's teeth. Ensure both brake shoes are correctly aligned with the wheel cylinder plungers, sitting flush against them. Finally, install the upper return spring, connecting the top of both brake shoes. Double-check that all springs are correctly tensioned and that all pins and cups are securely locked in place. Give the shoes a gentle wiggle to ensure they move freely but are still held firmly by the pins.

Step 7: Reassembling the Drum and Initial Adjustment

Carefully slide the brake drum back over the new brake shoes and onto the hub spindle. If there's resistance, ensure the shoes are fully retracted and centred. Reinstall the wheel bearing and then thread on the large hub nut. Tighten the hub nut until the drum just stops spinning freely, then back it off slightly – typically about a quarter to half a turn – to allow for slight play. This prevents overtightening, which can damage the bearing, but also ensures the drum is seated correctly. Insert a new split pin through the hub nut and spindle hole, then bend its ends to secure it firmly. Never reuse an old split pin. Finally, fit the dust cap back onto the hub, ensuring it's securely seated to protect the bearing from dirt and moisture.

Step 8: Final Adjustment and Handbrake Check

Once both sets of rear brake shoes have been renewed, it's time to adjust them. With the handbrake fully released, get into the car and repeatedly depress the brake pedal at least 20 to 25 times, or until the pedal feels firm. As you depress the pedal, the adjuster strut should be self-adjusting the lining-to-drum clearance. Have an assistant listen to the rear drums; if the adjuster strut is functioning correctly, a distinct clicking sound will be emitted from the drum area with each pedal depression. This clicking indicates the adjuster is extending, taking up the slack as the shoes bed in. Once the pedal feels firm and you no longer hear the clicking, you should check and, if necessary, adjust the handbrake cable from under the car. Most handbrake cables have an adjuster nut. Adjust it so that the handbrake engages firmly after about 3-5 clicks. Do not overtighten, as this can cause the shoes to drag.

Step 9: Reinstall Wheels and Final Torque

Carefully put your wheels back on the hub, hand-tighten the wheel bolts, and then lower the car from the axle stands using your jack. Once the car is on the ground, use your wheel brace or torque wrench to tighten all wheel bolts to the manufacturer's specified torque settings. This is crucial for safety and to prevent the wheels from coming loose or warping the brake drums.

Bedding In Your New Brake Shoes

After replacing your brake shoes, it's essential to 'bed them in' correctly. For the first 100-200 miles, avoid harsh or sudden braking. Instead, use gentle, progressive braking to allow the new shoe material to conform perfectly to the shape of the brake drum. This process ensures optimal contact, maximises braking efficiency, and extends the lifespan of your new components. You might notice a slight burning smell during the initial drives; this is normal as the new materials heat up and cure.

Signs of Worn Rear Brake Shoes and a Faulty Adjuster Strut

Knowing when to replace your rear brake shoes is key. Here are some common indicators:

• Grinding or Squealing Noises: A metallic grinding sound often indicates that the friction material has worn away, and the metal backing of the shoe is contacting the drum. Squealing can be an early warning sign or indicate worn hardware.
• Reduced Braking Performance: If your car takes longer to stop, or the brake pedal feels spongy or goes closer to the floor than usual, your shoes may be worn.
• Loose Handbrake: If your handbrake needs to be pulled up excessively high (more than 5-7 clicks) to engage, it's often a sign of worn shoes that the adjuster strut can no longer compensate for.
• Vibration When Braking: Can indicate warped drums or unevenly worn shoes.
• Visible Wear: During a wheel rotation or inspection, you might notice that the friction material on the shoes is very thin.
• No Clicking Sound During Adjustment: If, after replacement, the brake pedal adjustment doesn't produce the characteristic clicking sound from the adjuster strut, it indicates the strut itself might be faulty or improperly installed.

Frequently Asked Questions (FAQs)

How often should rear brake shoes be replaced?

Rear brake shoes generally last much longer than front brake pads because the front brakes do most of the work. Their lifespan varies significantly depending on driving style and conditions, but typically they can last anywhere from 60,000 to 100,000 miles or even more. Regular inspections are the best way to determine when they need replacing.

Can I replace just one side of the rear brake shoes?

No, it is crucial to always replace brake shoes on both sides of an axle (i.e., both rear wheels) at the same time. This ensures balanced braking and prevents the car from pulling to one side when you apply the brakes, which can be a serious safety hazard.

What if my adjuster strut isn't clicking during the adjustment process?

If you're not hearing the clicking sound from the adjuster strut when depressing the brake pedal, it's a strong indication that the self-adjustment mechanism isn't working. First, recheck that the adjuster strut, its lever, and spring are all correctly installed and oriented. Ensure nothing is binding or preventing the strut from extending. The longer fork of the strut must be behind the shoe. If the installation is correct, the adjuster strut itself might be faulty and need to be replaced.

Do I need to bleed the brakes after replacing rear brake shoes?

Typically, no. Replacing only the brake shoes does not open the hydraulic system, so you shouldn't need to bleed the brakes. However, if you replaced the wheel cylinder (due to a leak), then you absolutely must bleed the entire brake system to remove any air that entered the lines.

What's the difference between brake shoes and brake pads?

Brake shoes are used in drum brake systems, where they press outwards against the inside of a rotating drum to create friction. Brake pads are used in disc brake systems, where they clamp onto a rotating disc (rotor) to slow the vehicle down. Cars usually have disc brakes on the front and either disc or drum brakes on the rear.

Estimated Cost

The cost of new rear brake shoes can vary depending on your vehicle's make and model, as well as where you purchase them. Generally, you can expect to pay anywhere from £15 to £30 for a complete set of rear brake shoes, which often includes the adjuster strut and springs. Performing this job yourself will save you significantly on labour costs, which can easily run into hundreds of pounds at a garage.

By following this comprehensive guide, you've not only saved money but also gained valuable insight into your vehicle's braking system. Regular maintenance of your brakes, including the crucial adjuster strut, is vital for your vehicle's overall stopping power and your safety on the road. Drive safely!

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