Differential Re-Gear Kit for GM 8.5" with 4.11 Ratio and

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Drivetrain› Differentials and Rear-End Components

Zumbrota Drivetrain

Differential Re-Gear Kit for GM 8.5" with 4.11 Ratio and

Name: Differential Re-Gear Kit for GM 8.5" with 4.11 Ratio and
Brand: Zumbrota Drivetrain
SKU: YGK2339

$1,484.96

SKU: YGK2339

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Overview

The Zumbrota Drivetrain YGK2339 is a differential re-gear kit for GM 8.5” differentials. It includes a ring and pinion set, a Dura Grip positraction limited-slip differential with 28 splines, and all necessary installation parts. This kit features a 4.11 gear ratio, a 30-spline pinion gear, and 2.25" OD bearings. It is designed for compatibility with various models, including the 1970-1981 Firebird Trans Am and 1970-1977 GTO, as well as 25 other models or any hot-rodded vehicle with a GM 8.5” differential.

Show original supplier description

The Zumbrota Drivetrain YGK2339 is a comprehensive re-gear and limited-slip differential kit designed for GM 8.5” axle applications. This kit provides a significant upgrade for vehicles seeking improved performance and traction. Complementing the re-gear components is the Yukon Dura Grip positraction limited-slip differential (LSD). This LSD unit features 28 splines and is engineered to distribute torque effectively to both rear wheels, improving traction during acceleration and cornering, especially in slippery conditions. The kit is specified for GM 8.5” differentials, featuring a 30-spline pinion gear and a 10-bolt ring gear pattern. It also includes 2.25" OD bearings and all the necessary installation hardware to ensure a complete and proper setup. The fitment explicitly covers 1970-1981 Firebird Trans Am models and 1970-1977 GTO models, along with 25 other specific vehicles, or any custom build utilizing a GM 8.5” differential. This re-gear kit is a substantial upgrade for muscle cars and performance-oriented builds, offering a balance of improved off-the-line performance with the enhanced traction benefits of a limited-slip differential.

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.

Fitment

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Specifications

Brand	Zumbrota Drivetrain
Part Number	YGK2339
Category	Drivetrain

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