Moroso Coolant Expansion Tank Subaru WRX / STI 2008-2021 | 63871

The factory plastic expansion tank on a WRX or STI doesn't hold up forever — repeated heat cycles turn it yellow and brittle, and eventually it cracks. This Moroso tank is a direct bolt-in replacement, machined from fabricated aluminum instead of plastic, built to handle the heat that kills the factory unit without discoloring or failing.

It bolts in using the factory mounting points and includes a provision for the factory siphon hose, so there's no rerouting or fabrication needed at install. A billet aluminum cap with O-ring is included, and the tank itself can be left in natural aluminum finish or polished, chromed, painted, or powder coated to match the rest of the engine bay.

Key features and benefits

• Direct bolt-in replacement for the factory plastic tank
• Fabricated aluminum construction resists the heat that cracks and discolors factory tanks
• Includes provision for the factory siphon hose
• Billet aluminum cap with O-ring included