Drivetrain› Differentials and Rear-End Components

Richmond Gear/Motive Gear

Excel Ring & Pinion Gear Set GM 12Bolt 3.73 Ratio

$475.95

SKU: R01O 12BC373

In Stock
In Stock
Ships by Jun 7
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Richmond Gear 12BC373 is a ring and pinion gear set designed for GM 8.875-inch, 12-bolt car differentials. It features a 3.73 gear ratio, providing a balance of torque and efficiency suitable for street driving and performance applications. Constructed from premium 8620 steel, this set is built for durability. It includes a 30-spline pinion gear and a standard rotation for reliable driveline operation. This thin gear set requires a 3.90 or numerically higher ratio carrier for proper installation.

Fitment

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Specifications

BrandRichmond Gear/Motive Gear
Part NumberR01O 12BC373

Buy with Confidence

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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