YG GM12T-373 High Performance Ring & Pinion Gear Set 3.73 Ratio

In this review the Yukon Gear & Axle YG GM12T-373 ring and pinion set earns attention from owners of GM 12-bolt truck rears who need a durable, quiet gear change without a lot of fuss. The bottom line: this is a vehicle-specific, high performance 3.73 ratio set built to OEM fitment that balances strength and low noise, making it a practical upgrade for increased power or larger tires. The reviewer found the set easy to set up with the advertised surface finishes reducing run-in friction and heat under load.

Key Features

• Vehicle Specific Fit: Designed for GM 8.875 in 12-bolt truck rear housings so installation follows OEM fitment and reduces fitment surprises.
• 3.73 Ratio: The 3.73 ratio offers a useful balance of acceleration and drivability for trucks with added horsepower or larger tires.
• Quiet Running Design: Yukon uses modern gear tooth surface finishes and manufacturing methods to keep gear whine low under normal driving and towing loads.
• High Grade Steel: Both ring and pinion are made from premium steel and manufactured to exacting specs for durability in high torque conditions.
• Easy to Set Up: The parts are engineered with OEM spec fitment and clear machining that simplifies backlash and pattern setup during installation.
• One-Year Warranty: Standard one-year warranty coverage gives a basic level of protection against manufacturing defects.

Who It's For

This ring and pinion set is aimed squarely at owners of GM 12-bolt rear axle trucks with the 8.875 in carrier who want a reliable 3.73 final drive. It is a good choice for daily-driven trucks that have gained horsepower or larger tire sizes and need a gear change that keeps engine RPMs and drivability in check.

It is less suited for someone needing a custom-cut, racing-only ratio or those who require an extensively warrantied lifetime program without considering the optional Yukon Y.E.S. plans. Also, installers seeking a universal fit for multiple axle types should look elsewhere for broader compatibility.

Pros & Cons

Pros

• Vehicle-specific design simplifies installation and reduces fitment headaches for GM 12-bolt truck rears.
• Quiet running thanks to modern gear tooth surface finish that reduces friction and heat.
• Durable construction using high grade steel suitable for higher torque and larger tires.
• Comes with a one-year warranty and access to Yukon service plans for added peace of mind.

Cons

• Warranty is one year by default; lifetime coverage requires enrollment in optional Yukon programs.
• Not a universal fit - limited to GM 8.875 in 12-bolt truck rear applications only.

Specifications

Brand	Yukon Gear & Axle
Model	YG GM12T-373
Fit Type	Vehicle Specific (GM 8.875 in 12-bolt truck rear)
Gear Ratio	3.73
Ring & Pinion Set Type	High Performance, OEM spec fitment
Warranty	One-year manufacturer warranty (Yukon Y.E.S. plans available)

Our Verdict

The Yukon YG GM12T-373 3.73 ring and pinion is a sensible, high quality upgrade for GM 12-bolt truck owners who want a durable, quiet gear set that fits OEM specs. It represents good value for people adding horsepower or larger tires because of its durable steel construction, modern tooth finish, and straightforward fitment, though those wanting lifetime coverage should explore Yukon's extended plans.

Frequently Asked Questions

Will this fit my GM 12-bolt truck?
Yes, this set is made for GM 8.875 in 12-bolt truck rear carrier applications and is vehicle specific for that axle size.

What ratio is this set?
This ring and pinion set is a 3.73 final drive ratio, suitable for balancing acceleration and highway drivability.

Does it come with a warranty?
Yukon includes a one-year manufacturer warranty; additional coverage is available through Yukon Y.E.S. plans.