Subaru OEM Coolant Hose (05-09 Legacy - 30D) | 21204AA810

Overview

The Genuine Subaru OEM Coolant Hose (Part #21204AA810) is an exact-fit factory replacement designed for 2005–2009 Subaru Legacy 3.0 models. As an authentic OEM component, this coolant hose meets the precise engineering tolerances and material specifications set by Subaru, ensuring reliable coolant flow and long-term durability. If you're experiencing a leaking or deteriorating coolant hose on your Legacy, this is the correct OEM solution — no modifications required.

Key Features & Benefits

• Genuine Subaru OEM Part – Manufactured to Subaru's exact factory specifications for a perfect, guaranteed fit on compatible Legacy models.
• Exact-Fit Replacement – Drop-in installation with no cutting, clamping adjustments, or fitment guesswork; replaces the original hose precisely.
• OEM-Grade Materials – Constructed from factory-spec rubber compounds engineered to withstand the thermal cycling and pressure demands of Subaru's EZ30 engine cooling system.
• Maintains Cooling System Integrity – Proper coolant flow helps prevent overheating and protects the engine from heat-related damage.
• Factory Warranty Backed – Covered under Subaru's genuine parts warranty for added peace of mind.
• Direct OEM Cross-Reference – Replaces Subaru part number 21204AA810; no compatibility guesswork.

What's Included

• 1x Genuine Subaru OEM Coolant Hose – Part #21204AA810

Specifications

Fitment & Compatibility

This coolant hose is designed specifically for the following Subaru vehicles equipped with the 3.0L EZ30 engine (designation 30D):

Always verify your vehicle's VIN and engine code before ordering to confirm correct fitment. The "30D" designation refers specifically to the EZ30 engine variant.

Installation

This is a direct OEM replacement coolant hose. Installation involves draining the cooling system, removing the old hose and clamps, fitting the new hose in the factory position, and refilling with the correct Subaru coolant. While many experienced DIYers can complete this repair, we recommend having a qualified technician perform cooling system work to ensure proper torque and coolant fill procedures are followed. No modifications are required — this hose fits exactly like the original.