TOYOTA 91551-80616 Flange Bolt

The TOYOTA 91551-80616 (OEM superseded part number: 90105W0032) is a premium quality genuine OEM flange bolt designed and manufactured in accordance with Toyota's strict engineering standards. This fastener plays a critical role in securely and durably fastening various structural and mechanical assemblies of the vehicle.

Technical Features and Construction

Thanks to their specialized design, flange bolts provide an optimal fastening solution in automotive applications:

• Integrated Washer (Flange): The built-in flange beneath the bolt head distributes clamping force evenly across the contact surface, eliminating the need for a separate washer. This reduces the risk of surface damage and helps prevent loosening.
• High-Tensile Material: Manufactured from a high-grade steel alloy that withstands severe mechanical stress, shear forces, and vibration.
• Corrosion Protection: Features a specialized surface treatment providing effective protection against rust caused by moisture, road salt, and environmental elements.
• Precision Thread Design: Ensures an accurate fit and proper tightening torque without damaging the mating threads.

Function and Importance

Flange bolts are most commonly used in locations where vibrations and dynamic loads pose a risk of conventional bolts loosening (such as suspension components, the engine bay, transmission mounting, or exhaust system components). Genuine OEM Toyota parts guarantee tensile strength and dimensional accuracy that conform to factory specifications, which is essential for safe operation.

Signs of Wear or Failure

Although bolts are extremely durable components, they require replacement under certain circumstances:

• Corrosion and Rust: Surface rust can compromise the structural integrity of the bolt, which in extreme cases can lead to breakage.
• Thread Damage or Elongation: Overtightening or metal fatigue can deform threads or stretch the bolt shank, resulting in a loss of required clamping force.
• Deformation or Fracture: Severe mechanical impact (such as an accident or extreme road hazards) can bend or shear the bolt.
• Damaged Bolt Head: Rounded corners caused by improper tool use make future installation or removal difficult.