Adjusting drum brakes is a relatively simple task that can be completed with a few basic tools. However, it is important to follow the steps carefully to ensure that the brakes are properly adjusted. Failure to do so could result in decreased braking performance or even brake failure. Additionally, regular brake adjustments will help to extend the life of your brake pads and drums.
Before you begin, you will need to gather a few tools. These include a jack, jack stands, a lug wrench, a screwdriver, and a brake adjusting tool. Once you have your tools, you can begin the process. Next, loosen the lug nuts on the wheel that you will be adjusting. Do not remove the lug nuts completely.
Now, use the jack to raise the vehicle and place the jack stands under the frame. Once the vehicle is secure, you can remove the lug nuts and take off the wheel. Next, locate the brake adjusting star wheel. This is usually located on the back of the brake backing plate. Use the brake adjusting tool to turn the star wheel. You will need to turn the star wheel in the direction that is indicated by the arrow on the brake backing plate. As you turn the star wheel, you will feel the brake shoes move closer to the brake drum. Continue turning the star wheel until the brake shoes are just touching the brake drum.
Inspecting the Brake System
Before adjusting the drum brakes, it’s crucial to thoroughly inspect the brake system to identify any potential issues. This inspection involves several key steps to ensure the proper functioning and safety of your vehicle’s braking system.
1. Visual Examination:
Begin by visually inspecting all components of the brake system, including the brake calipers, pads, rotors, brake lines, and hoses. Look for any signs of wear, damage, or leaks. Check the brake fluid level and condition, ensuring it is at the correct level and free of contamination.
2. Brake Pad Thickness:
Inspect the brake pad thickness. Worn brake pads can reduce braking effectiveness and lead to damage to the rotors. Refer to your vehicle owner’s manual or consult a mechanic to determine the minimum recommended thickness for your brake pads.
3. Brake Rotor Condition:
Examine the brake rotors for any visible damage, such as cracks, warping, or excessive wear. Warped rotors can cause vibration during braking, while cracked rotors can compromise the integrity of the brake system.
4. Brake Line and Hose Inspection:
Check the brake lines and hoses for any signs of damage, corrosion, or leaks. Inspect for any cracks, bulges, or soft spots in the lines. Leaking brake lines can lead to loss of brake fluid and reduced braking performance.
Gathering the Necessary Tools
Tools Required:
To begin adjusting your drum brakes, you’ll need to gather the following tools:
| – Jack stands | – Lug wrench |
| – Socket wrench or combination wrench | – Brake cleaner |
| – Brake spring tool | – Drum brake adjusting spoon |
| – Feeler gauge (optional) | – Anti-seize compound (optional) |
Additional Tools for More Thorough Maintenance:
In addition to the essential tools listed above, you may also want to consider gathering the following for a more thorough brake inspection and repair:
- Brake pads
- Brake shoes
- Brake hardware kit
- Brake caliper
- Brake rotors
- Brake fluid
Safety Precautions:
Before starting any brake work, it is crucial to take the necessary safety precautions:
- Park the vehicle on a level, stable surface.
- Engage the parking brake.
- Place wheel chocks behind the wheels opposite the ones you’ll be working on.
- Wear safety glasses and gloves.
Loosening the Brake Drums
Before you can adjust the drum brakes, you need to loosen the brake drums. To do this, you will need a wheel brace or lug wrench.
- Loosen the lug nuts on the wheel that has the brake drum you need to adjust. Do not remove them completely.
- Lift the car and support it on jack stands.
- Remove the lug nuts by hand and remove the wheel.
- Locate the brake drum. It is the large, round metal part that is attached to the wheel hub.
- There are two or more small holes in the brake drum. Insert a small screwdriver or nail into one of the holes and pry the brake drum off the wheel hub.
- Repeat steps 5–7 for the other wheel with the brake drum you need to adjust.
Once the brake drums are loose, you can adjust them to the proper specs. Follow the instructions in the next section to do this.
Removing the Drums
The first step in adjusting a drum brake is to remove the drums. To do this, you will need to jack up the vehicle and remove the wheel. Once the wheel is removed, you will see a large metal drum that is attached to the wheel hub. To remove the drum, you will need to remove the cotter pin that is holding the axle nut in place. Once the cotter pin is removed, you can use a socket wrench to remove the axle nut. Once the axle nut is removed, you will be able to pull the drum off of the wheel hub.
There are a few things to keep in mind when removing the drums. First, the drums can be heavy, so be careful when lifting them. Second, the drums may be rusted or corroded, so you may need to use a hammer to break them loose. Finally, be careful not to damage the axle or the wheel hub when removing the drums.
Here are some tips for removing the drums:
- Use a penetrating oil to help loosen the rusted or corroded bolts.
- Use a hammer to tap the drum around the edges to help break it loose.
- Be careful not to damage the axle or the wheel hub when removing the drums.
| 1. | Jack up the vehicle and remove the wheel. |
| 2. | Remove the cotter pin that is holding the axle nut in place. |
| 3. | Use a socket wrench to remove the axle nut. |
| 4. | Pull the drum off of the wheel hub. |
Adjusting the Star Wheel
Tools You’ll Need
To adjust the star wheel, you’ll need the following tools:
- Flathead screwdriver
- 10mm socket wrench
Steps
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Park your car on a level surface and engage the parking brake.
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Locate the star wheel through the access hole in the backing plate behind each wheel. It’s typically located at the bottom of the brake drum.
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Insert the flathead screwdriver into the star wheel’s teeth and turn the wheel down (counterclockwise) to loosen the brake shoes, allowing the drum to spin more freely.
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If the drum is still too tight, continue turning the star wheel down in small increments until the drum spins smoothly by hand with a slight amount of drag.
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Checking Brake Shoe Clearance
To ensure the brake shoes are properly adjusted, follow these steps:
- Spin the wheel by hand and check the clearance between the brake shoe and the drum surface.
- Use a feeler gauge to measure the clearance, which should be approximately 0.010" (0.25 mm).
- If the clearance is too small, adjust the star wheel down further. If it’s too large, adjust the star wheel up slightly.
- Repeat this process until you achieve the desired clearance.
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Once the brake shoes are properly adjusted, tighten the locknut on the star wheel using the 10mm socket wrench.
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Repeat the adjustment process for the other rear wheel.
Retightening the Locknut
The final step in adjusting a drum brake involves retightening the locknut that secures the brake shoes in place. This step is crucial to ensure that the brakes function properly and prevent any potential safety hazards.
1. Tightening the Locknut
Using an appropriate wrench or socket, carefully tighten the locknut on the brake shoe adjuster. It is important to avoid overtightening the locknut, as this can damage the adjuster or the brake shoes. Aim for a firm and secure fit that allows the adjuster to move freely without any play.
2. Checking the Adjustment
Once the locknut is tightened, spin the wheel to check the brake adjustment. The brake shoes should lightly contact the brake drum, providing a slight resistance to rotation. If the brakes are too tight, the wheel will be difficult to turn. If they are too loose, the brakes will not be effective.
3. Adjusting the Slack
If the brakes are too tight or too loose, readjust the brake shoes by turning the adjuster. To tighten the brakes, turn the adjuster clockwise; to loosen them, turn counterclockwise. Spin the wheel after each adjustment to check the brake feel and make fine-tuning adjustments as needed.
4. Ensuring Proper Operation
Repeat the adjustment process until the brakes provide a smooth and balanced feel when applied. The wheels should spin freely when the brakes are not applied and stop or slow down effectively when the brakes are engaged. If you encounter any issues or are unsure about the adjustment, it is recommended to seek the assistance of a qualified mechanic.
5. Table: Brake Adjustment Torque Specifications
| Vehicle Make/Model | Locknut Torque (ft-lbs) |
|---|---|
| Ford F-150 | 18-24 |
| Chevrolet Silverado | 15-20 |
| Toyota Camry | 9-13 |
Replacing the Drums
1. Safety First: Engage the parking brake and chock the wheels opposite the drum being replaced.
2. Remove the Wheel: Loosen the lug nuts with a lug wrench, then remove them and the wheel.
3. Detach the Backing Plate: Remove the retaining bolts holding the backing plate in place. Carefully pry the backing plate away from the axle using a flat-head screwdriver or pry bar.
4. Remove the Drums: Slide the drums off the brake shoes. If they are stuck, tap them gently with a hammer and chisel.
5. Inspect the Brake Shoes: Check the brake shoes for wear, damage, or contamination. If necessary, replace the worn-out brake shoes.
6. Clean the Backing Plate: Remove any dirt, rust, or debris from the backing plate and axle hub using a wire brush or sandpaper.
7. **Prepare the New Drums:** Lubricate the brake shoe contact surfaces of the new drums with anti-squeal compound or brake grease. This prevents squealing and ensures proper braking performance.
8. Install the New Drums: Slide the new drums over the brake shoes and onto the axle hub.
9. Reattach the Backing Plate: Carefully position the backing plate and secure it with the retaining bolts.
10. Install the Wheel: Place the wheel on the hub and hand-tighten the lug nuts. Use a torque wrench to tighten the lug nuts to the specified torque.
11. Bleed the Brakes: If necessary, bleed the brakes to remove any air that may have entered the brake system during the replacement process.
12. Test Drive: Take the vehicle for a test drive and check if the brakes are working properly. Listen for any unusual noises or vibrations.
Testing the Adjustments
Once you have made the adjustments, it’s important to test them to ensure they are correct. Here’s how to do it:
9. Testing the Drum Brake Adjustments in Detail
To thoroughly test the drum brake adjustments, follow these steps:
- Check for excessive brake drag: Drive the vehicle and apply light pressure to the brakes. If the vehicle pulls to one side or the brakes feel sluggish, it indicates excessive brake drag.
- Check for uneven braking: Apply the brakes firmly and observe the vehicle’s behavior. If one wheel locks up before the others, it suggests uneven braking distribution.
- Ensure proper pedal feel: The brake pedal should provide firm and consistent resistance without feeling too spongy or mushy.
- Listen for any unusual noises: While driving or applying the brakes, pay attention to any grinding, squealing, or other abnormal sounds that may indicate a problem with the brake adjustment.
- Inspect the brake wear: Remove the brake drums and check the brake pads for even wear. Uneven wear patterns may indicate improper adjustments.
- Validate the difference in brake shoe wear: Remove both brake shoes and compare the difference in wear between the primary and secondary shoes. There should be a noticeable difference, indicating proper adjustment.
- Confirm even contact between brake shoes and drum: With the brake shoes installed, inspect the contact surface between the shoes and the inside of the brake drum. The contact should be even around the entire circumference.
- Measure the brake drum diameter: Use a brake drum micrometer to measure the diameter of the brake drum and compare it to the specifications provided by the vehicle manufacturer. Ensure that the drum is within acceptable tolerances.
- Verify brake shoe clearance: With the brake shoes installed and the star wheel adjuster loose, check the clearance between the shoes and the drum. This clearance should meet the manufacturer’s specifications to ensure proper operation.
If any of these tests indicate a problem with the brake adjustments, it’s important to re-adjust the brakes and retest them until proper operation is achieved.
Troubleshooting Common Issues
1. Brake Pedal Feels Spongy
Air in the brake lines can cause a spongy brake pedal. Bleed the brakes to remove any trapped air.
Note: If bleeding the brakes does not resolve the issue, there may be a leak in the brake system. Inspect the brake lines, master cylinder, and wheel cylinders for leaks.
2. Brake Pedal Pulsates
Pulsating brake pedal can be caused by warped brake drums or rotors. Have the brake drums or rotors inspected and replaced if necessary.
Note: Pulsating brake pedal can also be caused by uneven pad wear. Inspect the brake pads and replace them if they are worn unevenly.
3. Brake Pedal Is Hard To Press
A hard brake pedal can be caused by a faulty brake booster or master cylinder. Inspect the brake booster and master cylinder and replace them if necessary.
Note: A hard brake pedal can also be caused by a seized caliper or wheel cylinder. Inspect the calipers and wheel cylinders and replace them if they are seized.
4. Brake Pedal Goes To The Floor
A brake pedal that goes to the floor can be caused by a leak in the brake system. Inspect the brake lines, master cylinder, and wheel cylinders for leaks.
Note: A brake pedal that goes to the floor can also be caused by a faulty brake booster or master cylinder. Inspect the brake booster and master cylinder and replace them if necessary.
5. Brakes Squeal
Squealing brakes can be caused by worn brake pads. Inspect the brake pads and replace them if they are worn.
Note: Squealing brakes can also be caused by a contaminated brake system. Flush the brake fluid and replace the brake pads to resolve the issue.
6. Brakes Drag
Dragging brakes can be caused by a seized caliper or wheel cylinder. Inspect the calipers and wheel cylinders and replace them if they are seized.
Note: Dragging brakes can also be caused by a faulty brake booster or master cylinder. Inspect the brake booster and master cylinder and replace them if necessary.
7. Brakes Lock Up
Locking brakes can be caused by a faulty proportioning valve or ABS module. Inspect the proportioning valve and ABS module and replace them if necessary.
Note: Locking brakes can also be caused by a contaminated brake system. Flush the brake fluid and replace the brake pads to resolve the issue.
8. Brakes Feel Unbalanced
Unbalanced brakes can be caused by a faulty brake proportioning valve or ABS module. Inspect the proportioning valve and ABS module and replace them if necessary.
Note: Unbalanced brakes can also be caused by a leak in the brake system. Inspect the brake lines, master cylinder, and wheel cylinders for leaks.
9. Brakes Fade
Fading brakes can be caused by overheated brake pads or rotors. Allow the brakes to cool down before using them again.
Note: Fading brakes can also be caused by a contaminated brake system. Flush the brake fluid and replace the brake pads to resolve the issue.
10. Other Issues
In addition to the issues listed above, there are a number of other problems that can occur with drum brakes. These include:
- Brake dust
- Glazed brake pads
- Cracked or broken brake shoes
- Seized brake adjusters
- Leaking wheel cylinders
- Faulty parking brake cables
It is important to have your drum brakes inspected regularly by a qualified mechanic to prevent these problems from occurring.
How to Adjust a Drum Brake
Drum brakes are a type of brake system that is commonly used in older vehicles. They are also found on some newer vehicles, such as heavy-duty trucks and trailers. Drum brakes work by using a set of brake shoes to press against the inside of a rotating drum. This creates friction, which slows down the vehicle.
Drum brakes need to be adjusted periodically to ensure that they are working properly. This is a relatively simple process that can be done at home with a few basic tools. To adjust drum brakes, you will need the following:
*
- A jack
- Jack stands
- A lug wrench
- A screwdriver
- A brake adjustment tool
Once you have gathered your tools, follow these steps to adjust your drum brakes:
1.
Park your vehicle on a level surface and engage the parking brake.
2.
Loosen the lug nuts on the wheel that you will be adjusting.
3.
Raise the vehicle using the jack and secure it with the jack stands.
4.
Remove the lug nuts and wheel.
5.
Locate the brake adjustment star wheel. It is usually located on the back of the brake backing plate.
6.
Insert the brake adjustment tool into the star wheel and turn it until the brake shoes just make contact with the drum.
7.
Back off the star wheel 1/4 to 1/2 turn.
8.
Reinstall the wheel and lug nuts.
9.
Repeat steps 1-8 for the other wheel.
10.
Lower the vehicle and remove the jack stands.
People Also Ask About How to Adjust a Drum Brake
What are the signs that my drum brakes need to be adjusted?
There are a few signs that your drum brakes may need to be adjusted. These include:
- The brake pedal feels spongy.
- The vehicle pulls to one side when braking.
- The brakes make a squealing noise when applied.
Can I adjust drum brakes myself?
Yes, you can adjust drum brakes yourself with a few basic tools. However, if you are not comfortable working on your vehicle, it is best to have a qualified mechanic adjust your brakes.
How often should I adjust my drum brakes?
Drum brakes should be adjusted every 10,000 to 12,000 miles. However, this may vary depending on your driving habits and the condition of your brakes.
