Eaton 913A590 Detroit Truetrac LSD for Rear Dana 44 30-Spline 3.92+ Gear Ratios

Regular price: $717.99
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Product Specification:

SKU:EAT913A590

MPN: 913A590

Weight: 26.0 lb

Inventory: 12

Type: Differentials

Vehicle Fitment

1977-1979 Ford (Half-Ton Trucks, Vans, SUVs) with Rear Dana 44, 3.92 & up gear ratio
1971-2006 Jeep Cherokee / Grand Cherokee / Liberty / Scrambler / Wagoneer / Wrangler with Rear Dana 44, 3.92 & up gear ratio
1967-1980 International Harvester Half-Ton Trucks / Vans / SUVs with Rear Dana 44, 3.92 & up ratio
1993-2000 Isuzu 100 / 1100 series, 4x4 Half-Ton Pickups, Scouts, Travelers with Rear Dana 44, 3.92 & up ratio

Fitment Notes

Rear-axle only; not compatible with front Dana 44 applications.
Gear ratio must be **3.92 or numerically higher**; lower ratios are not supported.
Does not fit thick ring gears; only for non-thick ring gear configuration.
Must have 30-spline axle shafts and approx. 1.31-inch shaft diameter.

Features

Helical gear limited-slip design (Detroit Truetrac) for smooth, automatic torque transfer.
No wearable clutches or friction plates - maintenance-free.
Optimized for off-road & street use under high load conditions.
Rated for numerically high gear ratios to improve torque and performance.
Quiet operation due to helical-gear design.
Robust build quality from Eaton for strength & durability.
Dual-drilled ring-gear bolt holes for both 3/8" and 1/2" ring gear bolts; sleeves available for 7/16" bolts.
Wide vehicle compatibility across Jeep, Ford, ISUZU, IH, etc., when specs match.

Specifications

Differential Type: Limited-Slip (Detroit Truetrac)
Axle Type: Rear Dana 44
Spline Count: 30 splines
Axle Shaft Diameter: ~1.31 in
Ring Gear Size: 8.50 in
Gear Ratio Compatibility: 3.92 & up (numerically higher)
Weight: ~25.69 lb
Condition: For non-thick ring gear housings only

Included Components

1x Eaton Detroit Truetrac Differential unit (Part # 913A590)
Installation Instructions
Warranty Information

Product Description

The Eaton 913A590 Detroit Truetrac Limited-Slip Differential is built to upgrade rear Dana 44 axles with 30-spline shafts to a stronger, more capable unit when running 3.92 and numerically higher gear ratios. Using Eaton's helical Truetrac design, it provides smooth, quiet, and automatic torque biasing to the wheel with the most traction, without the harsh engagement of traditional lockers. Ideal for off-road, towing, restoration, and performance street applications.

This unit is intended for non-thick ring gear Dana 44 housings; thick-ring variants require modifications or alternate setups. Installation requires matching axle-shaft spline count (30 splines), correct shaft diameter (~1.31 in), and ring gear size of approximately 8.50 in.

Check your gear ratio: if it is 3.92 or numerically higher, this differential will operate correctly. Lower ratios are not supported. For fitment beyond the listed vehicle years, match axle specs thoroughly, as common variation exists across manufacturers and model years.