Torque Solution TS-SU-679S Billet Coolant Expansion Tank for 2002-07 Subaru WRX

Vehicle Fitment

• 2002-2007 Subaru WRX (EJ20/EJ25, AWD) - GD/GG chassis
• 2004-2021 Subaru WRX STI (EJ25/EJ257/EJ207, AWD) - GD/GG/GB/VA chassis
• 2004-2008 Subaru Forester XT (EJ255, AWD) - SG/SH chassis

Features

• Precision CNC-machined billet 6061-T6 aluminium construction

Specifications

• Material: Billet 6061-T6 aluminium
• Finish: Clear or black anodised (depending on variant) with branded logo
• Install position: Coolant expansion/overflow tank, direct-fit replacement
• Connection: Utilises OEM hose fittings/adapters (no custom hose required) in stock mounting location
• Drivetrain: All-wheel drive (AWD) only - applicable to specified WRX/STI/Forester XT models
• Fitment confirmed through 2021 for listed models; 2022+ coverage unconfirmed at time of listing

Included Components

• 1x billet aluminium coolant expansion tank (assembled)
• 2x M8 x 14 stainless steel button-head bolts
• Installation instructions and manufacturer warranty documentation

Product Description

The Torque Solution TS-SU-679S Billet Coolant Expansion Tank is engineered to upgrade the cooling system on performance-oriented Subaru EJ-engine platforms. By replacing the OEM plastic tank - which is prone to cracking, heat discoloration, and degradation over time - with a strong billet aluminium unit, this product improves both reliability and aesthetics in the engine bay. Especially useful for turbocharged WRX/STI and Forester XT models, this tank supports high-stress operation and helps maintain proper coolant system function under load.

Installation is straightforward: the billet tank bolts into the original mounting position and uses the OEM cap and hoses. No major fabrication is required, making this an ideal upgrade for performance builds or track-use vehicles. This tank is compatible with the 2002-07 WRX, 2004-21 WRX STI, and 2004-08 Forester XT (EJ series, AWD). As with any cooling system upgrade, verifying hose fitment and ensuring correct coolant burp procedure is recommended.

Fitment is confirmed through 2021 for the listed models; coverage for 2022 and later model years is currently unconfirmed at the time of this listing. Always verify your vehicle's engine code, chassis, and coolant routing before purchase to ensure compatibility.