Speedmaster Ford 9 in. Aluminum 28-Spline Helical Gear LSD Third Member Assembly 3.89:1

The Speedmaster Ford 9 in. Aluminum 28-Spline Helical Gear LSD Third Member Assembly (model 1-215-001-05) is a precision-engineered differential component designed for high-performance and custom automotive applications. This aluminum third member features a 28-spline helical gear configuration with a 3.89:1 ratio, making it suitable for vehicles requiring upgraded differential performance and traction control.

Built with aluminum construction for reduced weight and improved efficiency, this LSD (limited-slip differential) third member assembly is engineered for durability and consistent power delivery across demanding driving conditions. The helical gear design provides smooth, quiet operation and enhanced load distribution compared to traditional spur gears. Ideal for street performance, track use, and custom builds where precise gear ratio and differential function are critical to vehicle dynamics and acceleration.

Key Features & Benefits

• Aluminum Construction: Lightweight aluminum design reduces overall weight while maintaining structural integrity and durability.
• 28-Spline Helical Gear: Helical gear configuration delivers smooth, quiet operation and superior load distribution.
• 3.89:1 Gear Ratio: Precise ratio engineered for performance-focused applications requiring specific differential behavior.
• LSD Technology: Limited-slip differential design provides controlled traction and power distribution under acceleration.
• Ford 9 inch Compatible: Direct fit for Ford 9 inch differential housings in compatible vehicle platforms.

Specifications

Ideal Applications

• Street performance and custom vehicle builds
• Track and racing applications
• Drag racing and acceleration-focused builds
• Custom differential upgrades for traction control