Zumbrota Drivetrain

Spartan Locker for GM 8.5-Inch 28-Spline Axle

$661.89

SKU: SL GM8.5-28

In Stock
In Stock
Ships by Aug 31
Free Shipping over $200
$100 Minimum Order
30 Days Return

Description

The Spartan Locker is a mechanical differential locker that provides reliable 100% lockup traction for GM 8.5-inch axles with 28 spline counts. It is constructed from 9310 steel for enhanced strength. This locker is designed as a 'lunchbox' style upgrade, meaning it replaces the existing spiders within a standard carrier case, simplifying installation. Its revolutionary spring and pin design eliminates the need for thrust washers.

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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Available on iOS & Android

Specifications

BrandZumbrota Drivetrain
Part NumberSL GM8.5-28
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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