IAG Performance Chromoly Transfer Gears For 1:1 Transmission Subaru STI 04-05 | IAG-DRV-1000

Product Fitment: 

2004-2005 Subaru STI

Requires: Driveshaft Shop or ACPT driveshaft for proper fitment

The IAG Chromoly Transfer Gear Set is purpose-built to eliminate one of the biggest failure points in the STI 6-speed transmission—the output shaft. Designed for aggressive launches and high-horsepower applications, this upgraded gear set reinforces your drivetrain where it matters most, ensuring greater strength, reliability, and long-term performance.

Under hard acceleration, the OEM output shaft in the STI can twist and eventually snap—especially where the driveshaft yoke connects. The IAG Transfer Gear Set solves this problem by increasing the diameter of the output shaft and enlarging and lengthening the splines. The redesigned parts are engineered to eliminate the weak links in the factory design, allowing the system to reliably handle extreme torque loads.

The gear set is precision-machined from Chromoly steel, a high-strength alloy known for its toughness and fatigue resistance. This advanced material significantly improves torsional strength and durability, making it ideal for track, drag, and high-performance street use.

Features:

• 1:1 Gear Ratio (For 2004–2005 STI)
  Matches the OEM ratio while delivering unmatched strength.

• Upgraded Output Shaft
  Enlarged and lengthened splines reduce failure risk under high load.

• High-Strength Chromoly Gears
  Reinforced for sustained high-performance abuse.

• Aftermarket Yoke Compatibility
  Designed to work with Driveshaft Shop or ACPT performance driveshafts.

• Tested on 1200 WHP/800 WTQ Subaru Drag Cars
  Proven durability in extreme racing environments.

Included:

• Chromoly Driven Gear

• Chromoly Output Shaft

• Upgraded Yoke

• Heavy-Duty U-Joint

• U-Joint Outside Snap Rings

Note: This kit may produce some drivetrain "whine" due to the performance gear engagement style. This is normal and expected in high-performance setups.