Drivetrain› Differentials and Rear-End Components

Zumbrota Drivetrain

Rear Axle Kit, 30 Spline 29.75 Inch

$230.89

SKU: ZA K630139

Special Order
Special Order
Ships in 4–6 weeks
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$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Zumbrota Drivetrain rear axle kit is designed for GM 12-bolt passenger car differentials. It features 30 splines and a length of 29.75 inches. This kit is intended for rear installation and includes a 5-lug configuration.
Show original supplier description
The Zumbrota Drivetrain ZA K630139 is a rear axle kit engineered for GM 12-bolt passenger car differentials. This kit offers 30 splines and a precise length of 29.75 inches, ensuring proper fitment for rear axle applications. This comprehensive kit is designed for a 5-lug setup and includes essential components for installation, such as the wheel bearing, seal, differential cover gasket, studs, and lug nuts. It also features a 2.25-inch outer diameter wheel bearing for reliable performance. As a product from USA Standard Gear, this rear axle kit is built to meet the demands of drivetrain components, providing a durable and direct replacement solution.

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

BrandZumbrota Drivetrain
Part NumberZA K630139
CategoryDrivetrain
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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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