Drivetrain› Differentials and Rear-End Components

USA Standard (Yukon)

Rear Axle Kit Fits GM 12P Diff 30 Spline 29-3/4 Long

$230.89

SKU: U018 ZA K630139

In Stock
In Stock
Ships by Jun 9
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The USA Standard Gear ZA K630139 is a rear axle kit designed for GM 12-Bolt Passenger Car Differentials. It features 30 splines, a length of 29.75 inches, and a 5 on 4.75 inch lug pattern. This kit includes essential components such as a wheel bearing, seal, differential cover gasket, studs, and lug nuts to facilitate replacement, repair, or upgrade of axle shafts.

Fitment

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Specifications

BrandUSA Standard (Yukon)
Part NumberU018 ZA K630139

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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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