Subaru Forester Radiator: Specs, Fitment & Common Faults

Confirmed: Subaru has extended the warranty for a known head gasket issue on certain production dates, with the gasket replaced completely free of charge — worth checking your car's manufacture date plate and this specific leak location first.

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OEM Part Numbers

Manual gearbox, all engines	Standard radiator with no transmission cooling circuit
Lineartronic CVT, standard engines	A genuine factory oil-to-water CVT fluid cooler is fitted as standard, using the same coolant that runs through the engine — confirmed by Subaru as functionally adequate for normal use, though the CVT's known heat-related reliability issues (which led Subaru to extend the powertrain warranty to 10 years/100,000 miles on many 2010-2018 vehicles) mean this cooler's condition and cleanliness genuinely matters
Turbo engines (XT/WRX and similar)	An additional auxiliary transmission cooler is fitted alongside the standard oil-to-water unit specifically because of the extra heat generated by the higher-output engine — not fitted on naturally aspirated variants

Accuracy note: genuinely worth knowing: some Forester engines pair the radiator with an integrated oil cooler or a separate charge-air cooler depending on turbocharging — these aren't interchangeable, so confirm your exact engine spec before ordering.

The Part That Keeps Everything Else From Cooking

Nothing about this component is glamorous, but almost every serious engine failure that isn't wear-related traces back to a cooling system problem left unaddressed. Catching the early signs here is genuinely cheap insurance against a much bigger bill.

Before you buy: radiator size and design vary significantly by engine size, transmission type, and whether your car has air conditioning. Always confirm against your VIN before ordering.

What It Does

The radiator transfers heat from the engine coolant to the surrounding air, keeping engine temperature within a safe operating range. On automatic versions, it often also cools transmission fluid through a separate internal circuit — one more reason the correct part number matters so much here.

Subaru Forester Radiator reference plate

Confirmed: A Genuine Extended Warranty Worth Checking Your Car Against — Subaru Forester Radiator

This is genuinely worth checking directly if you're finding unexplained coolant drips: head gasket seepage on these engines has a characteristic, specific location worth checking first — drips appearing on the crossmember that the engine mounts attach to, with the bottom of the head itself feeling damp, particularly toward the driver's side. This is a well-documented failure point rather than a random leak location. Genuinely important to know: Subaru has extended the warranty specifically covering this known head gasket issue on certain production dates, with documented cases seeing the gasket replaced completely free of charge under this extension. It's worth checking the manufacture date plate inside the driver's door frame and asking a dealer directly whether your specific car falls within the extended coverage window before assuming you'll need to pay for this repair.

A genuinely useful diagnostic technique worth knowing if a standard test comes back negative: a standard hydrocarbon or block test can sometimes give a false negative even when a genuine head gasket leak is present. Using a no-spill coolant funnel fitted to the radiator cap opening while revving the engine and watching for bubbles has been documented catching leaks that a standard test missed. It's also genuinely worth knowing that the complete absence of visible exhaust smoke or a coolant smell doesn't reliably rule out a head gasket leak on these engines, since seepage can occur without those more obvious symptoms being present at all.

It's also genuinely worth knowing that a Subaru-recommended coolant conditioner additive can delay or reduce head gasket seepage temporarily, but this is a delaying measure rather than a genuine fix — the underlying gasket still needs proper replacement eventually. Real repair costs for this job have been documented in the region of £1,950 to £2,750 or more, worth factoring in when deciding whether to pursue warranty coverage or budget for the repair directly.

Faults, DIY Difficulty & Aftermarket Advice

These are the same regardless of make or model — see our full Radiator Guide for the three common failure modes, confirming fitment against your VIN, and OEM vs aftermarket guidance.

More Subaru Radiator

The same part, covered across other Subaru models.

Subaru Forester Radiator: Specs, Fitment & Common Faults

OEM Part Numbers

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Confirmed: A Genuine Extended Warranty Worth Checking Your Car Against — Subaru Forester Radiator