Drivetrain› Differentials and Rear-End Components

Zumbrota Drivetrain

8.8" IRS Rear Axle Assembly 3.31 Posi-traction

$2,999.89

SKU: RAA440-1557B-P

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INSTALL DIFFICULTY
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Moderate — 2–4 hours

Overview

The Zumbrota Drivetrain RAA440-1557B-P is a remanufactured rear axle assembly. It features an 8.8" IRS (Independent Rear Suspension) and a 3.31 gear ratio with a Posi-traction differential.

This axle assembly is designed for 2015-2023 Ford Mustang models. It is shipped in high-density plastic totes to prevent damage during transit.
Show original supplier description
The Zumbrota Drivetrain RAA440-1557B-P is a remanufactured rear axle assembly, engineered for precision and reliability. This unit is built around an 8.8-inch Independent Rear Suspension (IRS) system and comes equipped with a 3.31 gear ratio and a Posi-traction differential. Each axle assembly undergoes a rigorous remanufacturing process. Zumbrota Drivetrain inspects all internal components, including ring and pinions, internal gears, clutches, and carriers, ensuring 100% inspection. All bearings, seals, crush sleeves, pinion nuts, and shims are replaced with new parts. The housings are tested for surface wear and cracks, and then cleaned using a state-of-the-art hydro-blasting and rinsing process to restore them to an OEM finish. Precise gear backlash is set to ensure proper lubrication and quiet operation, with correct rolling torque established using inch-pound measurements for optimal setup and longevity. This axle assembly is specifically designed for 2015-2023 Ford Mustang models with 2.3L or 5.0L GAS engines. It is compatible with various sub-models including EcoBoost, EcoBoost Premium, GT, GT Premium, and GT 50 Years Limited Edition. Units are shipped in high-density plastic totes to help eliminate in-transit damage. Technical specifications include an 8.8" IRS axle type, a fluid capacity of 1.6 quarts, and requires non-synthetic 80w-90 fluid. The unit is not shipped with fluid and mounting hardware is not included. Please be aware of California Proposition 65 warnings associated with this product.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandZumbrota Drivetrain
Part NumberRAA440-1557B-P
CategoryDrivetrain
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