Truetrac 31 Spline Limited-Slip Differential

The Eaton Detroit Truetrac is a helical-gear style, limited-slip differential that maximizes wheel traction. It utilizes a patented design of parallel-axis planetary helix gears to provide quiet, automatic torque splitting without requiring maintenance. This differential is engineered for use in the Ford 8.8-inch axle and features a 31-spline count, making it suitable for various applications including drag racing, extreme off-roading, street use, and towing. With an axle shaft diameter of 1.32 inches and a ring gear size of 8.8 inches, the Detroit Truetrac is designed for robust performance. It is compatible with all ring gear ratios and is suitable for a wide range of vehicle usage, from on-road drag racing and restoration to off-road extreme use and rock crawling. It fits rear axles on passenger cars from 1986-2014, small trucks, minivans, and SUVs from 1983-2014, and half-ton trucks, vans, and SUVs from 1987-2014. The AmericanMuscle product page specifically lists fitment for 11-14 Mustang V6 models and 86-14 V8 Mustang models, with an exclusion for the 13-14 GT500. Installation notes are available, and it is recommended to consult the application guide for specific fitment details.