If your rear drum brakes are making a grinding noise, then they need to be replaced. Modern brake systems are designed so that they make a squealing sound when they become worn down. If this sound is ignored, then the next thing that you will hear is a grinding metal sound. This sound is indicative of the fact that the pads are completely worn down and replaced. Ignoring this sound can cause damage to the components in your brake system. Replacing rear drum brakes is a task that can be easily accomplished by just about anyone. But it does require careful attention to detail and the right tools. Here is a list of the tools that you are going to need to get the job done correctly.
Jack
Jack stands
Wrenches
Screwdriver
Pliers
Hammer
Large chisel
Brake spring pliers
Brake retaining tool
Dust mask
Brake shoes
White lithium grease
Turkey baster
Brake fluid
Drum Micrometer
Step One: Drain the Master Cylinder
Locate the master cylinder on your vehicle and remove approximately half of the brake fluid that it contains. This is done because the new shoes will be thicker then the old shoes and will push the extra brake fluid out of the master cylinder if it is filled to the max mark. The brake fluid can easily be removed using a turkey baster. This brake fluid should be discarded after it has been removed. You are going to be adding new brake fluid after the job has been completed.
Step Two: Remove the Vehicles Tires
Loosen the lug nuts on your tire and jack the car up according to the manufacturer’s instructions. Set the car on its jack stands and remove the lugs nuts and the corresponding tire. Make sure that you only do one tire at a time, so that you can use the opposite side as a reference if you get confused. You are now ready to work on the brakes.
Step Three: Remove the Brake Shoes
Look for a round clip. This clip was used when the car came off the assembly-line to hold the drum assembly in place and is completely useless now. Use pliers or wire cutters to cut it off. Now inspect the drum. If the drum is dragging against the drum shoes, then find the brake adjustment screw and turn it to back it off of the shoes. Also check the brake drum for rust or corrosion. If it is corroded and can’t be easily removed, then you may have to apply a lubricant such as WD-40 and lightly tap the axle flange with a hammer.
The next thing that you’ll want to do is to remove the parking brake cable and the springs that bind the shoes against the wheel cylinder. Depending on the model of your car, you may have to take additional brake hardware off to remove the shoes. You can now remove the brake shoes. It is important to remember that brake shoes should be done as a pair. If you need to replace one side, then go ahead and replace the other side as well.
Step Four: Inspect the Brake Drums
On the side of every brake drum is it’s surface diameter. Using your brake drum micrometer to ensure that the drum is with these specifications. If it exceeds this number, then the drum must be replaced. If it is within the limits, then check for cracks or heat spotting. Drums that are either cracked or heat spotted should be immediately replaced. Minor scoring on the brake drum can be removed with sandpaper, but grooves have to be removed using a professional grinding machine. Many auto part stores offer drum grinding services if you don’t own one.
Step Five: Install the New Brake Shoes
Put the brake shoes on and make sure that they are properly aligned. Now you can attach the self-adjustment spring and screw it down into position. Attach all the brake hardware that you had previously removed. After you have finished this you can reattach the parking brake cable. The final thing to be done is to reattach the hold-down springs and put the return springs on the brake shoe. Make sure that drum can move freely against the brake lining and put the wheels on. You can now take the car out for a little spin to make sure that everything is working the way it should.