Drivetrain› Differentials and Rear-End Components

Richmond Gear

3.73 Ratio Ring and Pinion Gear Set

$230.00

SKU: 836-GM85373

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In Stock
Ships by Aug 5
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INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Richmond Gear GM85373 is an Excel series ring and pinion gear set engineered for optimal performance and durability. Manufactured under Richmond's strict specifications, this set is designed by engineers with over 70 years of experience in gear design and manufacturing. The design, tooling, material selection (8620 Steel), and heat treat processes all carry Richmond's stamp of approval. This specific gear set features a 3.73 gear ratio, making it suitable for a wide range of applications. It is compatible with carriers ranging from 2.73 to 5.38. The set includes 30 pinion splines, requires 10 ring gear bolts, and uses 10 rear cover bolts, with a standard ring gear diameter of 8.5 inches. The application for this ring and pinion set includes 1972-2013 GM 8.5" and 8.6" rearends. It is also compatible with the 1980-1987 GM 8.5" corporate front end. Richmond Gear provides a 1-year warranty against manufacturing defects for this product.

MIA's Description

The Richmond Gear GM85373 is a 3.73 ratio ring and pinion gear set designed for GM 8.5" and 8.6" rearends from 1972-2013. It will also fit 1980-1987 GM 8.5" corporate front ends. This Excel gear set is manufactured to Richmond's exacting specifications, with their engineers overseeing the gear design, tooling, material selection, and heat treat recipes. It features 30 pinion splines, 10 ring gear bolts, 10 rear cover bolts, and an 8.5" ring gear diameter.

Fitment

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Specifications

BrandRichmond Gear
Part Number836-GM85373
CategoryDrivetrain

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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