What is the benefit of a 3.90 gear ratio?

A 3.90 gear ratio typically lowers the engine's RPMs at highway speeds compared to a stock ratio. This can lead to a quieter ride and potentially better fuel efficiency on longer drives.

What vehicles does this ring and pinion set fit?

This set is designed for GM 8.5-inch rear axles and fits a wide variety of vehicles, including models like the Chevrolet Avalanche, Cadillac Escalade, and Buick Electra, spanning many model years.

Does this ring and pinion set come with installation hardware?

This product includes the ring and pinion gears. Installation typically requires additional components such as bearings, seals, and shims, which are usually sold separately. Refer to the manufacturer's installation guide for a complete list of required parts.

Yukon Gear & Axle Ring & Pinion Gear Set 3.90 Ratio ZG GM8.5

Name: USA Standard Ring & Pinion Gear Set For GM 8.5in in a 3.90 Ratio
Brand: Yukon Gear & Axle
Price: 355.47 USD
Availability: InStock

USA Standard Ring & Pinion Gear Set For GM 8.5in in a 3.90 Ratio

$355.47

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Yukon Gear & Axle ring and pinion gear set for GM 8.5in diffs with a 3.90 ratio. Improves highway cruising comfort and fuel economy.

Key Features

Fits a wide range of GM vehicles with the 8.5-inch rear axle.
Features a 3.90 gear ratio for improved highway cruising.
Built to exceed OEM specifications.
Undergoes rigorous in-house quality evaluation for dimensional, material, and fitment accuracy.
Part number ZG GM8.5-390.

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Will this fit your vehicle?

Product Details

Yukon Gear & Axle is well-known for making solid drivetrain components, and this USA Standard Ring & Pinion gear set is no exception. If you're looking to change the final drive ratio in your GM 8.5-inch rear axle, this set offers a 3.90 ratio. This ratio is often chosen to bring down engine RPMs on the highway, which can make for a more comfortable ride and potentially improve fuel economy on longer trips.

These USA Standard gear sets are built to go beyond what the original equipment offered. Each set undergoes strict quality checks to make sure the dimensions, materials, and fitment all meet their standards. This attention to detail means you're getting a well-built part that's ready to perform. The 3.90 ratio is a popular choice for many trucks and SUVs that see a lot of road driving.

This gear set is designed to fit a wide range of GM vehicles equipped with the 8.5-inch rear axle, including models like the Chevrolet Avalanche, Cadillac Escalade, and Buick Electra. When installing a new ring and pinion, it's important to follow the manufacturer's instructions carefully, especially regarding gear pattern checking and break-in procedures, to ensure longevity and proper performance.