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Keep Your Classic Subaru Cool Under Pressure
The GrimmSpeed Radiator Hose Kit is built for the 2002 to 2007 Subaru WRX, 2004 to 2007 WRX STI, and 2002 to 2005 Impreza, replacing dry rotted factory rubber hoses with a heat resistant, fiber reinforced silicone design. As these older Subarus age, factory hoses become brittle and prone to cracking or splitting, which can leave you stranded with a cooling system failure. GRM405325 uses the same 5 ply silicone construction found across the GrimmSpeed hose kit lineup, reverse engineered from factory hoses for an exact fit with no trimming or kinking. Each black finished hose is embossed with the GrimmSpeed logo and paired with new stainless steel clamps, giving your classic Subaru a durable, factory style cooling system upgrade.
Key Features
- 5 ply silicone construction with fiber reinforcement between each layer
- 3D scanned for a perfect factory style fit
- Embedded GrimmSpeed logo on each hose
- Includes new stainless steel clamps for installation
- Improves cooling system durability versus factory rubber hoses
- Available in black finish
Fitment Table
| Year Range | Make | Model |
|---|---|---|
| 2002-2007 | Subaru | WRX |
| 2004-2007 | Subaru | WRX STI |
Specifications
| Detail | Value |
|---|---|
| Brand | GrimmSpeed |
| MPN | GRM405325 |
| Color | Black |
| Material | 5-Ply Reinforced Silicone |
| Number of Hoses | 2 |
| Clamps Included | Yes |
| UPC | Not published by manufacturer |
What's Included
- 1 upper radiator hose
- 1 lower radiator hose
- New stainless steel clamps for installation
About GrimmSpeed
GrimmSpeed is a Seattle based performance manufacturer that designs and builds parts specifically for the Subaru and import performance community. Every part is engineered, tested, and produced with a focus on real world durability, easy installation, and measurable performance gains, making GrimmSpeed a trusted name among WRX and STI owners nationwide.
FAQ
What is the GRM405325?The GRM405325 is a GrimmSpeed silicone radiator hose kit built for the 2002 to 2007 Subaru WRX and 2004 to 2007 WRX STI.
What material is GRM405325 made from?GRM405325 uses 5 ply reinforced silicone construction for improved heat and pressure resistance over factory rubber hoses.
Does GRM405325 fit the Impreza as well?Yes, GRM405325 also fits the 2002 to 2005 Subaru Impreza that shares the same cooling system layout.
Does GRM405325 require trimming during installation?No, GRM405325 is 3D scanned from factory hoses to install without trimming or kinking.
Does GRM405325 include clamps?Yes, GRM405325 includes new stainless steel clamps for a complete installation.
Why should I replace my factory hoses with GRM405325?Factory hoses on older Subarus become brittle over time and are prone to cracking, so GRM405325 offers a more durable, long term replacement.
Is GRM405325 available in colors other than black?GRM405325 is offered in black. A red version of this kit is available under a separate part number.
How many hoses are included with GRM405325?GRM405325 includes one upper hose and one lower hose.
Install Instructions
- Allow the engine to cool completely before beginning work.
- Drain the coolant system into an approved container.
- Loosen and remove the factory hose clamps at the radiator and engine connections.
- Remove the factory upper and lower radiator hoses.
- Install the new GRM405325 upper and lower hoses following the same routing as the factory hoses.
- Secure each connection using the included stainless steel clamps.
- Refill the cooling system with the appropriate coolant and bleed any trapped air.
- Start the engine and inspect all connections for leaks before normal use.
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