TOYOTA 90105-12174 Flange Bolt, Brake Caliper

The Toyota 90105-12174 is a genuine OEM high-strength flange bolt (washer-based hex head bolt) primarily designed for securing critical brake system components, such as the brake caliper. Genuine OEM parts guarantee precise fitment, maximum safety, and long service life in accordance with factory specifications.

Function and Importance in the Vehicle

Brake caliper mounting bolts are subjected to extremely high mechanical and thermal loads due to the forces generated during braking. The washer-based flange design plays a crucial role:

• Even Load Distribution: The integrated flange (washer) distributes clamping force over a larger surface area, reducing the risk of surface damage to fastened components.
• Resistance to Loosening: The increased contact surface area provides higher friction, preventing the bolt from vibrating loose.
• High Tensile Strength: Manufactured from specially hardened steel to withstand high shear and tensile forces.

Technical Specifications

• Manufacturer: TOYOTA (Genuine OEM part)
• Part Type: Flange Hex Head Bolt (Bolt, Washer Based)
• Primary Application: Brake caliper mounting, suspension components
• Material: High-strength, heat-treated alloy steel
• Surface Protection: Corrosion-resistant zinc-plated or phosphated coating for protection against environmental influences and winter road salt

Maintenance and Replacement Information

Brake caliper bolts must be thoroughly inspected during every brake caliper or brake disc replacement. Bolt replacement is recommended in the following cases:

• Thread Damage or Elongation: Overstretched or stripped threads cannot provide the required clamping force.
• Corrosion: Significant rust weakens the structural integrity of the material.
• Manufacturer Specification: In many cases, brake caliper mounting bolts are single-use (torque-to-yield) fasteners that must be replaced with a new genuine part upon removal to ensure safety.