why does my BMW 3 Series E90/E91 (2005-2012) shake when I brake

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is parked on a level surface and engage the parking brake.
• Disconnect the battery to ensure safety while working on brake components.

2. Remove Wheels

• Using a socket set, loosen the lug nuts while the vehicle is on the ground.
• Lift the vehicle using a jack and secure it with jack stands.
• Completely remove the lug nuts and take off the wheels.

3. Inspect and Replace Brake Components

• Inspect Brake Rotors:

  • Measure rotor thickness with a micrometer; compare with manufacturer specifications.
  • If warped beyond specs (typically 0.002 inches), proceed to replace.

• Replace Rotors (if necessary):

  • Remove caliper mounting bolts and slide caliper off the rotor.
  • Remove old rotor and install the new rotor, ensuring it is clean and free of debris.

• Inspect and Replace Brake Pads:

  • Remove the old brake pads from the caliper bracket.
  • Apply brake lubricant to the backing of the new pads and install them into the caliper bracket.

4. Reassemble and Torque Components

• Reinstall the caliper over the new pads and new rotor.
• Tighten the caliper mounting bolts to the manufacturer’s torque specifications (usually around 25-35 ft-lbs).
• Reinstall the wheels and hand-tighten the lug nuts.

5. Lower Vehicle and Final Checks

• Lower the vehicle back to the ground and torque the lug nuts to the manufacturer’s specifications (usually 80-100 ft-lbs).
• Reconnect the battery and ensure all tools are removed from the engine bay.