Zumbrota Drivetrain

USA Standard 8.875" 3.73 Ratio Ring & Pinion Gear Set

$350.89

SKU: ZG GM12P-373

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

Description

The USA Standard Ring & Pinion "thin" gear set is engineered for GM 12-bolt passenger car differentials, providing a 3.73 gear ratio. This set includes an 8.875-inch ring gear diameter and a 30-spline pinion, requiring 12 ring gear bolts. The "thin" design is optimized for compatibility with carriers that have a 4.10 ratio or numerically higher, ensuring proper meshing and performance. Installation of this gear set involves precise setup and backlash adjustment to ensure optimal performance and longevity within the differential. It is a component within the broader drivetrain system.

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 NumberZG GM12P-373
CategoryDrivetrain

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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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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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