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Drivetrain› Differentials and Rear-End Components

Zumbrota Drivetrain

Spartan Locker for AMC Model 20

Name: Spartan Locker for AMC Model 20
Brand: Zumbrota Drivetrain
SKU: SL M20-29

$719.89

SKU: SL M20-29

Free Shipping over $200

$100 Minimum Order

Non-Returnable Item

DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Spartan Locker is a differential locker for AMC Model 20 applications. It is constructed from 9310 steel for enhanced strength and replaces the spiders in a standard carrier case. This mechanical locker provides reliable 100% lockup and includes a heavy-duty cross pin shaft.

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The Spartan Locker is a mechanical differential locker designed for AMC Model 20 applications with 29 spline axles. Manufactured by USA Standard Gear, this locker offers a reliable 100% lockup solution for improved traction in demanding conditions. It is constructed from durable 9310 steel, providing added strength and longevity. This Spartan Locker replaces the standard spider gears within the carrier case, delivering a robust locking mechanism. It comes complete with a heavy-duty cross pin shaft for enhanced durability. The product is identified by the part number SL M20-29 and is a component of the Zumbrota Drivetrain catalog.

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	SL M20-29
Category	Drivetrain

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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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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