Ensuring your Mitsubishi ASX's brakes are in top condition is essential for safe driving and vehicle longevity. Brake pads are a critical component of the braking system, designed to create friction against the brake rotors, slowing and stopping your vehicle. Over time, these pads wear down and require replacement to maintain effective braking performance. While replacing brake pads may seem like a complex task, with the right tools, safety precautions, and step-by-step guidance, it is a manageable do-it-yourself project that can save you time and money. This comprehensive guide will walk you through the entire brake pad replacement process for your Mitsubishi ASX, providing detailed instructions, helpful tips, and important safety information.

Understanding Brake Pads and When to Replace Them

Brake pads are made of a friction material bonded to a backing plate. When you press the brake pedal, the calipers squeeze the brake pads against the rotors, generating friction that slows your vehicle. Over time, the friction material wears down, reducing braking efficiency and potentially damaging other brake components.

Signs Your Brake Pads Need Replacement

  • Squeaking or Squealing Noises: Many brake pads have built-in wear indicators that emit a high-pitched noise when the pads are worn.
  • Reduced Braking Performance: Longer stopping distances or a spongy brake pedal can indicate worn pads.
  • Vibration or Pulsation: Shaking or pulsating when braking may signal warped rotors or uneven pad wear.
  • Visual Inspection: If the pad thickness is less than 3 millimeters (about 1/8 inch), it’s time to replace them.

Regular inspection every 10,000 to 15,000 kilometers (6,000 to 9,000 miles) is recommended, but always consult your Mitsubishi ASX owner’s manual for specific maintenance intervals.

Essential Tools and Materials

Before beginning the brake pad replacement, gather all necessary tools and materials. Having everything ready will streamline the process and reduce frustration.

  • New Brake Pads: Ensure they are compatible with your Mitsubishi ASX model and year. OEM (Original Equipment Manufacturer) pads are recommended for optimal fit and performance.
  • Car Jack and Jack Stands: A hydraulic floor jack and sturdy jack stands to safely lift and support your vehicle.
  • Lug Wrench or Impact Wrench: For loosening and tightening wheel lug nuts.
  • Socket Set or Wrenches: Typically, a 12mm or 14mm socket is needed for caliper bolts, but verify your model’s specifications.
  • C-Clamp or Brake Caliper Piston Tool: To compress the caliper piston and make room for the new pads.
  • Brake Cleaner: A specialized spray to clean brake components and remove brake dust.
  • Wire Brush: For cleaning rust and debris from caliper brackets and rotors.
  • Anti-Seize Compound or Brake Grease: To lubricate caliper bolts and pad contact points, preventing noise and ensuring smooth operation.
  • Gloves and Safety Glasses: Protect your hands and eyes from dirt, chemicals, and debris.
  • Torque Wrench: To tighten lug nuts and caliper bolts to manufacturer-recommended torque specifications.
  • Service Manual or Repair Guide: Helpful for reference on torque specs and any model-specific procedures.

Step-by-Step Brake Pad Replacement Process

1. Prepare Your Vehicle

Start by parking your Mitsubishi ASX on a level surface, away from traffic. Engage the parking brake to prevent the vehicle from rolling. It’s advisable to work on one side at a time, starting with the front or rear brakes depending on your vehicle’s configuration.

Before lifting the vehicle, slightly loosen the lug nuts on the wheel you will be working on. Do not remove them completely yet; this prevents the wheel from spinning while you loosen the nuts.

2. Safely Lift and Support the Vehicle

Using the hydraulic jack, lift the vehicle at the manufacturer’s recommended lifting points, typically located near the wheel wells. Once raised, securely place jack stands under the vehicle to support its weight safely. Never rely solely on the jack for support.

3. Remove the Wheel

Fully remove the loosened lug nuts and carefully take off the wheel, setting it aside where it won’t be damaged. This exposes the brake assembly, including the rotor, caliper, and brake pads.

4. Inspect the Brake Components

Before removing the brake pads, take a moment to inspect the rotor surface for grooves, rust, or warping. If the rotors are damaged, they may require resurfacing or replacement. Also, check brake lines for leaks or damage.

5. Remove the Brake Caliper

The brake caliper holds the brake pads against the rotor. Locate the caliper bolts—usually two—and use the appropriate socket or wrench to remove them. Be careful not to strain the brake hose connected to the caliper.

Once unbolted, gently lift the caliper off the rotor. Support the caliper using a bungee cord or wire hanger attached to the suspension to avoid damaging the brake hose.

6. Remove the Old Brake Pads

Slide the old brake pads out of the caliper bracket. They may be held in place by clips or retaining pins, so check for these and remove accordingly. Take note of how the pads are oriented for correct installation of the new ones.

7. Clean and Prepare the Caliper Assembly

Use brake cleaner to thoroughly clean the caliper, caliper bracket, and rotor surface. A wire brush can help remove stubborn rust or debris. Cleanliness ensures proper function and extends component life.

8. Compress the Caliper Piston

The caliper piston must be pushed back to accommodate the thickness of the new brake pads. Place a C-clamp or brake caliper tool over the piston and slowly compress it until it is fully retracted into the caliper housing. This step is crucial to prevent brake drag and ensure proper pad fitment.

Important: Before compressing the piston, inspect the brake fluid reservoir under the hood. Compressing the piston will push brake fluid back into the reservoir, which could cause overflow if the fluid level is already high. Remove some fluid if necessary.

9. Install the New Brake Pads

Apply a thin layer of brake grease to the back of the new brake pads and any contact points on the caliper bracket to reduce noise and ensure smooth operation. Avoid getting grease on the friction material.

Slide the new brake pads into the caliper bracket in the same orientation as the old ones. Ensure they sit securely and flush against the rotor.

10. Reattach the Brake Caliper

Carefully reposition the caliper over the new brake pads and rotor. Reinstall and tighten the caliper bolts to the manufacturer’s torque specifications using a torque wrench. Proper torque prevents bolt loosening and maintains braking performance.

11. Reinstall the Wheel

Place the wheel back onto the hub and hand-tighten the lug nuts. Lower the vehicle carefully from the jack stands using the jack.

12. Tighten the Lug Nuts

Once the car is on the ground, use a torque wrench to tighten the lug nuts in a star or crisscross pattern to the recommended torque value. This ensures even pressure and prevents wheel warping.

13. Test the Brake Pedal

Before taking your Mitsubishi ASX for a drive, sit in the driver’s seat and pump the brake pedal several times. This action helps the brake pads seat properly against the rotors and restores normal brake pedal pressure.

Check the brake fluid level again and top up if necessary. If the pedal feels soft or goes to the floor, there may be air trapped in the brake lines, requiring a brake bleed procedure, which may be best handled by a professional.

Additional Tips for Brake Pad Replacement

  • Replace Brake Pads in Pairs: Always replace brake pads on both sides of the axle simultaneously to maintain balanced braking.
  • Consider Rotor Replacement or Resurfacing: If rotors are worn or damaged, replacing or resurfacing them along with pads improves braking efficiency and pad longevity.
  • Use Quality Parts: Investing in high-quality brake pads and components ensures better performance and safety.
  • Dispose of Old Pads Properly: Brake pads may contain hazardous materials. Follow local regulations for disposal or recycling.
  • Wear Protective Gear: Brake dust can be harmful if inhaled; wearing a mask, gloves, and safety glasses is recommended.
  • Follow Manufacturer Specifications: Consult your Mitsubishi ASX owner’s manual for torque specs, brake fluid type, and other model-specific guidelines.

When to Seek Professional Help

While this guide is designed for DIY enthusiasts with some mechanical aptitude, certain situations warrant professional assistance:

  • If you encounter seized bolts or damaged components requiring specialized tools.
  • If brake fluid leaks are detected or the brake pedal feels unusually soft after replacement.
  • If you are uncomfortable or unsure about performing any part of the procedure safely.
  • If your vehicle has complex braking systems like ABS (Anti-lock Braking System), which may require advanced diagnostics after service.

Professional mechanics have the expertise and equipment to ensure your brake system is serviced correctly, safeguarding your safety on the road.

Conclusion

Regular maintenance and timely replacement of brake pads are vital to keep your Mitsubishi ASX’s braking system functioning optimally. Performing brake pad replacement yourself can be rewarding and economical, provided you follow safety protocols and step-by-step instructions carefully. By understanding the components involved, using the right tools, and taking your time during the process, you can confidently restore your vehicle’s braking performance. Always prioritize safety, and when in doubt, consult a professional mechanic.

For more detailed guidance, troubleshooting tips, and recommendations tailored to your Mitsubishi ASX, refer to the official service manual or trusted automotive resources.