Subaru OEM Transmission Bell Housing STI 2004-2006 | 31020AA000

Overview

The Genuine Subaru OEM Transmission Bell Housing (Part #31020AA000) is a factory-original replacement component engineered specifically for the 2004–2006 Subaru STI. Designed to exact OEM tolerances, this bell housing ensures a precise, rattle-free fit between the engine block and transmission—critical for maintaining the drivetrain integrity that the STI platform demands. Choosing a genuine OEM part guarantees compatibility, factory-level durability, and preserves your vehicle's performance characteristics without compromise.

Key Features & Benefits

• Genuine Subaru OEM Quality — Manufactured to factory specifications, ensuring exact fitment and long-term reliability you can trust.
• Exact-Fit Design — Engineered specifically for the 2004–2006 STI drivetrain, eliminating the guesswork and fitment issues associated with aftermarket alternatives.
• Factory-Grade Materials — Constructed from the same high-strength materials used in original production, providing durability under the high-torque demands of the EJ257 engine.
• Drivetrain Integrity — Maintains proper alignment between the engine and transmission, which is essential for smooth power transfer and protection of adjacent drivetrain components.
• Factory Warranty Eligible — As a genuine Subaru OEM part, it is backed by Subaru's standard OEM parts warranty when installed by an authorized dealer.
• Direct OEM Replacement — Drop-in replacement for the original bell housing; no modifications required.

What's Included

• 1x Genuine Subaru OEM Transmission Bell Housing (Part #31020AA000)

Specifications

Fitment & Compatibility

This bell housing is a direct OEM replacement verified for the following Subaru vehicles:

2004-2006 Subaru STI

Always verify your vehicle's VIN and current part number before ordering to confirm compatibility. Cross-reference OEM part number 31020AA000 with your existing component.

Installation

Installation of the transmission bell housing requires removal of the transmission from the vehicle and is considered an intermediate-to-advanced level repair. Professional installation by a qualified Subaru technician or experienced drivetrain specialist is strongly recommended. Proper torque specifications and gasket sealing procedures should be followed per the Subaru factory service manual for the 2004–2006 STI.