The Eaton Detroit Truetrac Differential (Part #915A550) is a heavy-duty, helical-gear limited-slip differential built for Ford 10.25"/10.30" full-float rear axles with 35-spline shafts. Designed for maximum traction, durability, and reliability, the Truetrac’s proven all-gear design automatically distributes torque to the wheel with the most grip—without clutches, friction plates, or the need for maintenance.

Engineered for high-torque applications such as ¾-ton and 1-ton Ford trucks, vans, and SUVs, the Truetrac is ideal for towing, hauling, and off-road performance. It provides smooth operation on the highway and enhanced control in demanding conditions such as mud, snow, and rock crawling.

Note: For full-float applications only. Eaton recommends using a quality GL-5 rated 80W-90 petroleum-mineral based gear oil. Do not use synthetic oils or friction modifiers.

Features:

• Helical-gear, torque-biasing limited-slip differential for automatic traction control

• All-gear, maintenance-free design—no clutch packs to wear out

• Smooth, quiet performance on-road with reliable traction off-road

• Compatible with all gear ratios for Ford 10.25" and 10.30" full-float axles

• Built to handle high torque loads in heavy-duty applications

• Designed for long service life with minimal maintenance requirements

Specifications

Fitment:
Designed for Ford full-float 10.25" and 10.30" rear axles used in heavy-duty trucks and vans.

• 1985–2019: Ford ¾-Ton Trucks, Vans, SUVs – Rear Ford 10.25"/10.30" (Full Float)

• 1985–2019: Ford 1-Ton Trucks, Vans, Wagons, and Cab & Chassis – Rear Ford 10.25"/10.30" (Full Float)

Ideal Usage:

• Off-Road: Rock Crawl, Light Trail, Extreme Off-Road, Work Truck / Towing

• On Road: Street & Muscle, Circle Track, Drag Racing, Restoration, Work Truck / Towing

This Part Fits: