How to Compress an Emergency Brake Spring
Working on your own brakes can be satisfying but compressing the emergency brake spring is one of the most challenging tasks. The high tension in the coiled spring fights against compression, putting you at risk of muscle strains or getting caught in the coils. Having the right emergency brake tool makes the job much easier and safer. This guide will walk you through the entire process of compressing your emergency brake spring using proper technique and precautionary measures.
Here’s a quick step-by-step guide:
- Chock the wheels and lift the vehicle using a floor jack at the proper jacking points. Place jack stands underneath for safety.
- Remove the rear wheels for clear access to the brake assembly.
- Disconnect the brake cables from the caliper mechanism.
- Remove any retaining clips, bolts or pins securing the caliper housing.
- Clean all components with brake cleaner spray.
- Insert an emergency brake tool bar into the caliper to brace against the spring.
- Slowly compress the spring using body weight on the brake tool until bungee cords can wrap around the caliper to hold it compressed.
- With the spring compressed, remove the old spring and install the new replacement.
- Recompress the new spring with the brake tool and wrap bungees to hold it.
- Reinstall all the mounting hardware and components in reverse order.
Understanding Emergency Brake Springs
Emergency brake springs, sometimes called parking brake springs, provide the clamping force needed to keep your rear brakes engaged when the parking brake is activated. The high-carbon steel alloy coiled spring sits compressed inside the brake caliper.
When you pull the parking brake lever or switch, the cables attached to the caliper mechanism allow the compressed spring to expand. This expansion forces the brake pads against the rotor. When you release the parking brake, the mechanism compresses the spring again.
| Component | Function |
|---|---|
| Parking brake lever / switch | Activates brake cables to release compressed spring |
| Cables | Connected to caliper mechanism, allow spring expansion |
| Emergency brake spring | Provides clamping force to engage brakes |
| Caliper mechanism | Houses and compresses spring; adjusts brake pads |
After years of use, these springs lose their mechanical properties and tension. Replacing them is necessary to keep your parking brake working properly.
Gather the Right Tools
Compressing the emergency brake spring by hand is nearly impossible and extremely unsafe. Specialized tools help make spring compression controlled and safe.
The most important things you’ll need are:
- Emergency brake tool – A dedicated brake tool like the Lisle 44210 is specially designed to compress brake springs. The bar reaches through the caliper housing to safely contain the spring.
- Bungee cords – Also called shock cords, bungee cords temporarily hold the compressed spring. Wrap them around the brake assembly.
- Brake cleaner – This specialty cleaner removes debris and lubricates brake components to aid disassembly. Spray it liberally on any rusted or stuck hardware.
You’ll also need basic hand tools like wrenches, screwdrivers, pliers, gloves, and safety glasses. Refer to your vehicle’s service manual for details on any special tools or fasteners.
Step-by-Step Instructions
Follow these steps to safely replace your emergency brake spring:
1. Chock the Wheels
Before working underneath your vehicle, chock the front wheels to prevent accidental rolling. Engine vibrations can dislodge an unattended jack. Chocking adds an extra measure of safety.
2. Jack Up the Vehicle
Using a hydraulic floor jack, lift the vehicle at its designated jacking points near the rear tires. Secure the vehicle on jack stands for safe access to the wheel assembly.
3. Remove the Rear Wheels
With the brake rotor now accessible, remove the rear wheels. This gives you room to maneuver during spring compression.
4. Disconnect the Cables
Locate the brake cable ends fitted into the caliper housing. Carefully disconnect them from the caliper mechanism. Removing tension from these cables is necessary for spring compression.
5. Remove Fasteners
Refer to your manual to locate and systematically remove any retaining clips, bolts, or pins that secure the caliper housing. These usually require only basic hand tools for removal.
6. Clean Components
Use a brake cleaner spray to blast away any built-up grime or debris around the caliper and brake hardware. Lubricating the components helps later reassembly go smoothly.
7. Insert Emergency Brake Tool
Fit the emergency brake tool bar into the caliper opening. Position it to brace against the spring inside. Ensure the tool’s notch captures the spring securely.
8. Compress the Spring
Brace your body weight to push the brake tool bar forward, leveraging its notch to compress the spring. Move slowly to avoid uncontrolled release if the spring slips. Compress until bungee cords can wrap around the caliper to hold it.
9. Remove Old Spring
With the compressed spring temporarily held by the bungee cords, remove the emergency brake tool. You can now slide the compressed spring out from its brake pads easily.
10. Install New Spring
Carefully fit the new, uncompressed replacement spring back into the caliper. Ensure its end hooks properly engage their mount points.
11. Recompress Spring
Reinsert the emergency brake tool. Use your body weight again to slowly compress the new spring. Have your assistant wrap bungee cords around the caliper to temporarily hold it compressed.
12. Reassemble Components
Finally, reverse your disassembly steps. Refit any hardware, cables, and clips you removed earlier. Check your manual so each fastener secures back to factory spec.
13. Repeat on Other Side
If replacing springs on both rear wheels, repeat this entire process on the opposite side. Work carefully on each side before lowering the vehicle.
Final Safety Checks
Before driving, test the parking brake switch engagement. Ensure your newly-compressed springs apply enough force to securely hold the vehicle. Carefully remove the jack stands and lower the vehicle. Lastly, remove the wheel chocks. Check your work again to make certain everything functions properly before driving away.
FAQs
What strength bungee cord holds a compressed spring?
Very strong. Look for cords rated at least 700-1000 lbs breaking strength. Wrap two of these in opposing directions around the caliper for redundancy.
Can I compress the spring without a brake tool?
No. Attempting spring compression by improvising with things like screwdrivers is extremely unsafe. Only use an actual emergency brake tool designed for this job.
Do I need professional help for this job?
If you’re a novice, it can be challenging. Consider having an experienced mechanic guide you on your first spring replacement for safety.
How often do these springs need replacement?
Inspect them every brake service. They typically last at least 3-5 years before losing adequate tension. Replace them proactively before parking brake issues arise.
Compressing your parking brake spring enables you to restore proper brake function. Just be sure to use specialty brake tools and proper jacking techniques. With caution and patience, you can take care of this maintenance task yourself. Performing repairs boosts your self-reliance and saves on costly service bills.
