Parts for your 2015 Subaru Forester-Head gasket

2015 Subaru Forester head gasket — what it does and when it matters

Yes, the 2015 Subaru Forester uses a head gasket. Technical documentation confirms it: the Subaru Forester (SJ) 2014–2018 Factory Service Manual for the FB25 (2.5‑litre) and FA20F (2.0‑litre turbo) engines, Subaru’s Technical Information System (workshop procedures and torque specs), and the Genuine Subaru Parts Catalogue for MY2015 all list multi‑layer steel cylinder head gaskets between the aluminium block and cylinder heads on these engines. So the head gasket is absolutely relevant on a 2015 Forester.

The head gasket’s job is straightforward but critical. It seals the combustion chambers to hold compression, and it keeps engine oil and coolant in their own passages so they don’t mix. On the FB25 and FA20F boxer engines, the gasket is an MLS (multi‑layer steel) design that copes well with heat cycles and the unique clamping loads of a flat‑four layout.

There’s no scheduled service interval just for a head gasket, but good servicing habits dramatically reduce the chance of trouble. Keeping the cooling system healthy is the big one: correct Subaru long‑life blue coolant (mixed properly), no air pockets after refills, a sound radiator cap, clean radiator fins, and fans that kick in when they should. Overheating is the main head‑gasket killer, so anything that prevents a temperature spike helps the gasket live a long life.

• Common warning signs owners watch for:
  • Persistent coolant loss or damp staining at the block‑to‑head seam
  • White exhaust mist once warm, sweet coolant smell, or bubbles in the overflow
  • Unexplained overheating, rough cold starts, or milky contamination under the oil cap

If a gasket does fail, proper repair means more than just the gasket. A workshop following Subaru service manual procedures will check head flatness, surface finish, and fastener condition, then use the correct torque‑angle sequence. Many technicians also replace head bolts if they’re out of spec, and refresh supporting parts that make sense while it’s open—thermostat, hoses, spark plugs, PCV, fresh oil and filter, and new coolant. On these chain‑driven FB/FA engines there’s no timing belt to replace, but access considerations still make “while you’re there” items smart value.

For everyday servicing, a Forester that sees fresh coolant at the recommended interval (Subaru’s long‑life blue is typically up to 11 years/220,000 km—check the owner’s manual for local AU/NZ guidance), clean oil, and a cooling system check each service is far less likely to ever need a head‑gasket job.

Popular questions about 2015 Subaru Forester head gaskets

Do 2015 Foresters still have head‑gasket issues?
Compared with older EJ engines, the FB25 and FA20F use improved MLS gaskets and revised cooling, so widespread failures are much less common. Problems do happen, usually after overheating or neglected coolant. A well‑serviced 2015 Forester in AU/NZ conditions is typically trouble‑free.

What are the early signs of a failing head gasket?
Coolant loss with no obvious leak, bubbles in the overflow, random overheating, rough cold starts, or white exhaust once warm are the usual red flags. Oil that looks like a milkshake or a persistent sweet smell can also point to a breach. Any of these signs merit a cooling‑system pressure test and combustion‑gas check.

Is head‑gasket replacement covered by warranty or recall?
There’s no broad recall for 2015 Forester head gaskets. Coverage depends on warranty status and service history. In Australia and New Zealand, consumer law/guarantees may assist in specific cases, but assessment is case‑by‑case through the dealer or an independent specialist.