Torque Solution TS-SU-604 Urethane Rear Diff Bushings 2008-2021 WRX/STI Forester

Vehicle Fitment

• 2008-2014 Subaru Impreza WRX (2.5L EJ255 H4 Turbo, AWD) - Sedan and Hatchback
• 2015-2021 Subaru WRX (2.0L FA20DIT H4 Turbo, AWD) - Sedan
• 2008-2014 Subaru Impreza WRX STI (2.5L EJ257 H4 Turbo, AWD) - Sedan and Hatchback
• 2015-2021 Subaru WRX STI (2.5L EJ257 H4 Turbo, AWD) - Sedan
• 2009-2013 Subaru Forester XT (2.5L EJ255 H4 Turbo, AWD)

Fitment Notes

• Rear differential bushing inserts only - installs into existing OEM rear differential mount housings
• 75A durometer polyurethane - street and track suitable; mild NVH increase over OEM rubber expected
• For a more comprehensive full lockdown system (2008-2014 WRX/STI only) see PN TS-SU-603
• Direct OEM replacement - no chassis modification required

Features

• Reduces rear differential movement under hard acceleration and gear changes for improved transmission feedback and chassis rigidity
• Eliminates the "clunk" during aggressive shifts caused by OEM rubber differential bushing compliance
• 75A durometer polyurethane bridges the gap between soft OEM rubber and harsh solid mounts - street and track suitable
• Improves power transfer to the wheels by reducing energy lost to differential float and chassis flex
• Street and track torture tested; made in the USA by Torque Solution; Limited Lifetime Warranty

Specifications

• Part Type: Rear Differential Bushing Kit (Insert Style)
• Material: 75A Durometer Polyurethane
• Compatible Engines: EJ255 2.5L H4 Turbo, EJ257 2.5L H4 Turbo, FA20DIT 2.0L H4 Turbo
• Drivetrain: AWD
• Fitment: Direct OEM Replacement (installs into existing housings)

Included Components

• Complete set of 75A Durometer Polyurethane Rear Differential Bushing Inserts

Product Description

The Torque Solution TS-SU-604 is a 75A durometer polyurethane rear differential bushing kit covering the 2008-2021 Subaru WRX, 2008-2021 WRX STI, and 2009-2013 Forester XT. The OEM rubber rear differential bushings allow the differential to flex and float under acceleration and braking loads - producing the characteristic clunk during hard shifts and absorbing power that should be going to the wheels. These polyurethane inserts replace the inner rubber material within the existing OEM differential mount housings, significantly reducing that movement and improving drivetrain feedback without requiring any chassis modification.

The 75A durometer formulation provides a meaningful performance upgrade over the OEM rubber while remaining street-drivable - unlike solid mounts, it won't introduce excessive NVH into the cabin. For owners of the 2008-2014 WRX/STI seeking a more comprehensive solution that targets all differential mount locations simultaneously, the full lockdown system (TS-SU-603) is also available. Backed by Torque Solution's Limited Lifetime Warranty and made in the USA.