Speedmaster Ford 9 in. Aluminum 28-Spline Helical Gear LSD Third Member Assembly 3.00:1 Ratio

The Speedmaster Ford 9 in. Aluminum LSD Third Member Assembly is a precision limited-slip differential carrier designed for Ford 9-inch rear axles. This third member features 28-spline helical gears and a 3.00:1 gear ratio, combining aluminum construction with helical gear technology to deliver smooth power transfer and enhanced traction across a range of driving conditions. The assembly is engineered for street and strip applications where reliable differential function and consistent performance are essential.

The 28-spline configuration ensures robust engagement with compatible Ford 9-inch axle shafts, while the 3.00:1 ratio provides a balanced gear set suitable for general-purpose performance driving. The helical gear design reduces noise and improves efficiency compared to straight-cut alternatives, making this assembly ideal for drivers seeking a drop-in LSD solution that maintains OEM compatibility. Whether upgrading a classic muscle car, hot rod, or performance street machine, this third member offers a direct replacement option that enhances differential lock-up characteristics without requiring extensive axle modifications.

Key Features & Benefits

• 28-Spline Helical Gears: Precision-cut helical gears reduce noise and deliver smooth, efficient power transfer in the Ford 9-inch differential.
• 3.00:1 Gear Ratio: Balanced ratio designed for general-purpose performance and street driving applications.
• Aluminum Construction: Lightweight aluminum housing reduces unsprung weight while maintaining structural integrity.
• Ford 9-Inch Compatible: Direct fit third member assembly for standard Ford 9-inch rear axles with 28-spline shafts.
• Limited-Slip Differential: LSD carrier improves traction by allowing controlled slip between wheels for enhanced cornering and acceleration.

Specifications

Ideal Applications

• Classic muscle car and hot rod rear axle upgrades
• Performance street machines requiring improved traction
• General-purpose Ford 9-inch rear end differential replacement
• Off-road and weekend warrior vehicles seeking LSD functionality