Head gasket failures on EJ25 engines in the 2000-2009 Subaru Legacy can lead to external oil/coolant leaks or internal coolant/combustion gas mixing.
Reviewed by SubaruReview Editorial Team · Last reviewed 2026-05-15 · Editorial standards
How this problem ranks against the other documented Legacy failures — cost, severity, and DIY difficulty at a glance.
| Problem | Years | Severity | Repair cost | DIY |
|---|---|---|---|---|
| EJ25 Head Gasket Failure (2000-2009 Legacy) (this page) | 2000-2009 | Major | $1,500–$2,500 | 4/5 |
| Subaru Legacy GT EJ255 Turbocharger Lubrication Failure | 2005-2009 | Critical | $1,800–$8,500 | 4/5 |
This is one of several documented Legacy problems we track, and it fits inside the broader Engine Guides guide. If you're weighing repair against replacement, cross-check the Subaru repair-cost database and any open NHTSA recalls on your VIN before booking a shop.
The multi-layer steel (MLS) head gaskets on EJ25 engines, particularly early designs, are prone to failure. This allows combustion gasses to leak into the cooling system, or oil/coolant to leak externally, often visible as oil seepage around the cylinder heads.
The original equipment (OE) head gaskets on naturally aspirated EJ25 engines were susceptible to premature failure due to material and design shortcomings, specifically in the sealing beads between the coolant/oil passages and combustion chamber.
The original equipment (OE) head gaskets on naturally aspirated EJ25 engines were susceptible to premature failure due to material and design shortcomings, specifically in the sealing beads between the coolant/oil passages and combustion chamber.
National average $1,500–$2,500. Cost assumes replacement of both head gaskets, timing belt, water pump, and associated seals/gaskets. Higher end includes cylinder head machining if warpage is present.
Difficulty 4/5. Replace head gaskets with updated multi-layer steel (MLS) gaskets, such as Subaru Part No. 11044AA642 (right) and 11044AA633 (left), or equivalent aftermarket MLS gaskets.
External oil or coolant leaks from cylinder heads; White smoke from exhaust; Overheating; Coolant disappearing without visible leaks; Bubbles in coolant reservoir; Sweet smell of burning coolant
Owners typically pay $1,500–$2,500 at an independent Subaru shop, parts and labor included. Our Subaru Head Gasket Replacement Cost guide breaks the job down by parts, labor hours, and where the money actually goes.
The same generation also sees Subaru Legacy GT EJ255 Turbocharger Lubrication Failure. Both are documented with symptoms, cost, and a permanent-fix walkthrough — see the full list in the Legacy hub.
Cross-check NHTSA campaign 18V-846, which covers FA20 Valve Spring Fracture on 2012-2014 BRZ/Forester XT/WRX/Legacy. Recall work is free at any Subaru dealer — always run your VIN before paying for the fix.
We rate it 4/5 on our DIY scale. Most owners come out ahead with an independent Subaru shop; read labor-hour benchmarks in the repair-costs hub before you commit tools and a weekend.
It's part of our Engine Guides cluster, which collects every article covering the same system as this failure.
Same EJ-family boxer — the failure mode carries across every chassis this engine shipped in.
Same EJ-family boxer — the failure mode carries across every chassis this engine shipped in.
EJ, FA, FB, and EZ boxer deep-dives — the engine background this failure sits inside.
Dig into the Problems Database to plan your next maintenance sprint, or browse every model hub for buyer's guides, generation breakdowns, and known-issue lists.