Subaru OEM
Genuine Subaru OEM Radiator Cap 45137AE003 - WRX STI
2015–2021 Subaru WRX STI (VA)
Overview
The Genuine Subaru OEM Radiator Cap (Part # 45137AE003) is the factory-correct engine coolant reservoir cap designed for a wide range of Subaru models including the WRX, STI, Forester, Impreza, Outback, Legacy, and Crosstrek. As a critical component of your Subaru's cooling system, this OEM radiator cap maintains precise system pressure to prevent coolant loss, overheating, and air pocket cavitation at the water pump. Choosing a genuine Subaru part guarantees an exact fit, factory-spec pressure rating, and long-term reliability — no guesswork, no adapters, no compromises.
Key Features & Benefits
- Genuine Subaru OEM Quality — Manufactured to Subaru factory specifications for guaranteed fit, form, and function. No aftermarket guessing games.
- Correct Pressure Rating — Maintains factory-spec cooling system pressure to raise the coolant boiling point, preventing overheating and protecting your engine under demanding conditions.
- Prevents Coolant Loss & Cavitation — A properly sealed, pressure-rated cap eliminates air pockets at the water pump and stops coolant from escaping the system.
- Exact OEM Replacement — Directly replaces worn, cracked, or leaking original caps with zero modification required.
- Supersedes Legacy Part Numbers — Updates and replaces earlier Subaru part numbers 45137AE000, 45137AE001, and 45137AE002, ensuring you receive the latest revised OEM spec.
- Broad Multi-Model Compatibility — A single genuine part that covers 7 Subaru models and over 800 vehicle variants across nearly three decades of production.
- Manufacturer Warranty — Backed by Subaru's manufacturer warranty for added peace of mind.
What's Included
- 1x Genuine Subaru OEM Radiator / Engine Coolant Reservoir Cap (Part # 45137AE003)
Specifications
| Part Number | 45137AE003 |
|---|---|
| Supersedes | 45137AE000, 45137AE001, 45137AE002 |
| Part Type | Radiator Cap / Engine Coolant Reservoir Cap |
| System | Engine Cooling |
| Brand | Genuine Subaru OEM |
| Quantity Required | 1 per vehicle |
| MSRP | $18.05 |
| Warranty | Subaru Manufacturer Warranty |
Fitment & Compatibility
This Genuine Subaru OEM Radiator Cap fits 7 Subaru models across 805+ vehicle variants. See the compatibility table below:
| Model | Year Range |
|---|---|
| Subaru WRX | 2002 – 2026 |
| Subaru STI | 2004 – 2021 |
| Subaru Impreza | 1999 – 2026 |
| Subaru Forester | 1999 – 2025 |
| Subaru Outback | 1999 – 2026 |
| Subaru Legacy | 1999 – 2026 |
| Subaru Crosstrek | 2013 – 2026 |
Always verify fitment using your 17-digit VIN at parts.subaru.com or consult your Subaru retailer to confirm compatibility for your specific trim level and model year.
Installation
This is a direct OEM replacement — no tools, drilling, or modification required. Simply ensure the cooling system is fully cooled before removing the old cap, inspect the reservoir neck for debris or damage, then press and twist the new cap into place until it locks. For vehicles experiencing persistent coolant loss or overheating, inspect hoses and the reservoir for damage before replacement. Professional installation is not required but is recommended if cooling system issues persist.
Frequently Asked Questions
Is this a genuine Subaru part? Yes — Part # 45137AE003 is a Genuine Subaru OEM component, not an aftermarket replica.
What part numbers does this replace? This cap supersedes 45137AE000, 45137AE001, and 45137AE002 — it is the latest and most current Subaru OEM revision.
Does this fit both the WRX and WRX STI? Yes — this cap is compatible with the Subaru WRX (2002–2026) and Subaru STI (2004–2021).
Does it come with a warranty? Yes — this Genuine Subaru part is covered by Subaru's manufacturer warranty. Contact your retailer for warranty details.