Parts for your 2017 Subaru Forester-Exhaust gasket

2017 Subaru Forester exhaust gasket — what it does, where it fits, and when to replace

Yes, an exhaust gasket is used on the 2017 Subaru Forester. Technical sources confirm multiple gaskets are fitted from factory. The Subaru Service Manual for 2017MY Forester (Engine/Exhaust sections) specifies replacing exhaust gaskets whenever joints are disturbed, and the Subaru Electronic Parts Catalogue (EPC/FAST) lists gaskets at the cylinder-head-to-exhaust-manifold, manifold/front-pipe “donut” joint, mid-pipe and muffler flanges, and—on the XT—turbo/up-pipe and turbo/downpipe. Those references make it clear an exhaust gasket is absolutely relevant to this model, whether it’s the 2.5i (FB25) or the turbo XT (FA20F).

On this Forester, the exhaust gaskets seal the high‑temperature joints so exhaust gases don’t leak before the catalytic converters and sensors can do their job. Good sealing keeps things quiet, prevents fumes from creeping into the cabin, protects oxygen sensor readings for proper fuel trim, and avoids that raspy tick that ruins an early‑morning start. Subaru typically uses multi‑layer steel (MLS) gaskets at the manifold flanges and a compressible graphite/steel “donut” at the spring‑bolt joint to handle movement and heat cycling.

For servicing, the factory guidance is simple: if a joint is undone, fit a new gasket. Reusing flattened or heat‑soaked gaskets risks leaks, check‑engine lights (like P0420/P2096 due to skewed O2 data), and premature hardware corrosion. Owners in Australia and New Zealand often see the front donut and rear flange gaskets go first thanks to coastal air and plenty of short trips.

• Common leak clues: ticking on cold start that softens hot, a sooty ring at a flange, whiffs of exhaust under load, or a louder note from the tail.
• Best practice: use OEM‑quality MLS or graphite donut gaskets, clean and flatten mating faces, replace rusty spring bolts/studs, and tighten to the Service Manual spec and sequence.
• After any exhaust work: warm the car through a heat cycle, then recheck for seepage and retighten hardware if specified.

Forester XT owners should note there are additional gaskets at the turbo interfaces, heat is higher there, so fresh gaskets and intact heat shields matter even more. Regardless of trim, keeping those sealing rings in good nick keeps the Forester quiet, efficient, and happy on long Kiwi or Aussie road trips.

Popular questions

Does the 2017 Forester have multiple exhaust gaskets, and where are they?
Yes. There are gaskets at the cylinder head to manifold, the manifold/front pipe spring‑joint (donut), and the rear/mid‑pipe flanges. Turbo XT models also have gaskets at the up‑pipe to turbo and turbo to downpipe. These points are shown in the Subaru EPC and covered in the Service Manual removal/installation procedures.

How often should exhaust gaskets be replaced on a 2017 Forester?
They’re not a time‑or‑kilometre service item. Replace them whenever a joint is opened or if there’s a leak. In coastal Aussie/NZ conditions, the front donut and rear flange gaskets commonly need attention once hardware corrodes or past 100–150,000 km, but inspection during routine servicing is the smart play.

Can exhaust gaskets be reused on this model?
Subaru’s workshop procedures specify installing new gaskets on reassembly. Reusing flattened or heat‑cycled gaskets risks leaks, noise, and incorrect O2 readings. Fresh gaskets are cheap insurance compared with chasing a persistent exhaust tick or a catalyst efficiency fault code.