Eaton Detroit Truetrac 30 Spline Differential GM 8.5"/8.6" 2.73 & Up - 913A481

The Eaton Detroit Truetrac Differential (Part #913A481) is a premium helical-gear limited-slip differential engineered for GM 8.5"/8.6" axles with 30-spline shafts and 2.73 & up gear ratios. Built with precision and durability in mind, the Truetrac delivers smooth, automatic torque transfer for superior traction and control—without the need for wearable clutch packs or friction additives.

Designed for both performance and utility applications, this differential enhances handling and stability across a variety of driving conditions—from street and drag racing to rock crawling and towing. Its all-gear design ensures maintenance-free operation and consistent performance over time.

Note: Eaton differentials for GM 8.5"/8.6" axles require special bearings. Vehicles prior to 1999 generally use bearing LM102949 and race LM102911 (2.89" bore), while 1999–2013 models use bearing LM603049 and race LM603012 (3.06" bore). Manual locking hubs are recommended for front axle setups.

Features:

• Helical-gear, torque-biasing design for smooth, automatic engagement

• Maintenance-free operation with no clutch packs to wear out

• Durable, all-gear construction for long-lasting performance

• Ideal for on-road and off-road traction enhancement

• Compatible with GM 8.5"/8.6" 10-bolt axles (2.73 & up gear ratios)

• Recommended bearing specifications provided for correct fitment

Specifications

Fitment:
Compatible with GM 8.5"/8.6" 10-bolt rear axles, covering a wide range of vehicles from passenger cars to heavy-duty trucks and SUVs.

• 1988–1996: GM, Chevrolet, Pontiac, Buick, Oldsmobile – Passenger Cars (GM 10-Bolt C-Clip)

• 1988–2013: GM – ¾-Ton Trucks (Rear GM 10-Bolt C-Clip)

• 1988–2007: GM – ½-Ton Trucks & Vans (Rear GM 10-Bolt C-Clip)

• 2005–2007: Saab 9-7X (Rear 8.6 Axle)

• 2006–2009: Hummer H1, H2, H3 (Rear Axle, 2.73 & Up)

Ideal Usage:

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

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

This Part Fits: