Parts for your 2015 Subaru Outback-Exhaust gasket

2015 Subaru Outback exhaust gasket — what it is and when to sort it

Yes, the 2015 Subaru Outback uses exhaust gaskets. Subaru’s Factory Service Manual for the 2015 Legacy/Outback (Engine > Exhaust) specifies manifold-to-cylinder head gaskets and front exhaust pipe ring “donut” gaskets, with replacement required any time they’re removed. Subaru’s OEM parts catalogues for the 2015 Outback (FB25 2.5i and EZ36 3.6R) also list multi-layer steel manifold gaskets and crush-ring/graphite-metal pipe gaskets at the manifold-to-front pipe and mid-pipe joints. Aftermarket technical catalogues (e.g., Fel‑Pro, Victor Reinz) mirror these listings, confirming the part is fitted across this model range.

On this Outback, exhaust gaskets keep the system gas-tight from the cylinder head through to the catalytic converter and mid-pipe. They manage heat, reduce noise and vibration, and help the oxygen sensors read cleanly so the ECU can keep fuel trims on point. The manifold gaskets are typically multi-layer steel for durability under heat cycling, while the pipe joints use crush-type ring gaskets to flex with engine movement and thermal expansion without leaking.

• Common locations: manifold-to-head, manifold-to-front pipe (donut), and selected mid-pipe flange joints.

They’re not a routine “every X kilometres” service item. Instead, they should be replaced whenever that section of the exhaust is disturbed, or if there’s evidence of a leak. Signs include a ticking or puffing noise on cold start, exhaust smell in the cabin or around the engine bay, soot marks at the flange, poor fuel economy, or a check engine light related to fuel trims or catalyst efficiency.

• Best practice when replacing: always use new gaskets and the specified self-locking nuts/spring bolts, follow the Subaru torque sequence and specs, and ensure flanges are clean and true. Avoid sealants unless the service manual explicitly permits them.

For Aussie and Kiwi conditions—especially coastal areas—expect more corrosion. Penetrating oil, heat, and replacing any crusty studs or spring bolts will save headaches. Support the exhaust so it’s not hanging on the manifold while you line things up, and inspect rubber hangers and heat shields while you’re under there. A tidy, sealed system keeps the car compliant for a WOF or roadworthy check and prevents fumes from sneaking into the cabin.

DIY is achievable with stands and the right sockets, but seized hardware can turn into a mission. Many owners leave manifold-end work to a workshop, since access and hot hardware can be tricky.

Does the 2015 Subaru Outback have exhaust gaskets, and where are they?

It does. There are multi-layer steel gaskets between the cylinder heads and the exhaust manifolds, plus crush-ring “donut” gaskets at the manifold-to-front pipe connection and at some mid-pipe flange joints. Both the Subaru service manual and OEM parts diagrams specify these for the 2.5i and 3.6R.

How often should exhaust gaskets be replaced on this model?

They’re replaced on condition or whenever disturbed—there’s no fixed interval. If a section is removed, fit new gaskets and any self-locking nuts/spring bolts. If you notice ticking on cold start, soot at a joint, or cabin fumes, it’s time to inspect and likely replace.

Is it safe to drive with a leaking exhaust gasket?

Not ideal. A leak can push fumes toward the cabin, skew oxygen sensor readings, make the car noisy, and risk a WOF/roadworthy fail. Short trips to a workshop are usually OK with ventilation, but it’s best to repair promptly.