Parts for your 2016 Subaru Xv-Radiator cap

2016 Subaru XV radiator cap — purpose, checks, and when to replace

Based on technical references — the Subaru Factory Service Manual (Cooling System section for the GP/GP7 XV) and the Subaru Genuine Parts Catalogue — the 2016 Subaru XV (FB20 2.0L) does use a radiator cap. It’s a pressure-type cap mounted on the radiator filler neck, with a specified rating of about 108 kPa (1.1 bar). Typical Subaru part listings show this as a genuine cap (commonly referenced under 45137AE003 for naturally aspirated FB engines). So, yes — a radiator cap is very much relevant on this model.

On the 2016 XV, the radiator cap does more than just close the filler neck. It regulates system pressure so coolant can run hotter without boiling, which helps prevent overheating on steep climbs, hot days, or in stop–start traffic. Inside the cap are two valves: one holds pressure to raise the boiling point, the other lets coolant return from the overflow bottle as things cool down, keeping the system topped up and air-free. If the cap can’t hold the correct pressure, the engine can run hotter than it should, if it can’t pull coolant back, the system can ingest air and start playing up.

As part of routine servicing, the cap deserves a quick once-over under the bonnet:

• Check the rubber seals for nicks, flattening, or hardening.
• Make sure the spring feels firm and the valve moves freely.
• Look for dried coolant stains around the filler neck or overflow hose.
• Ask for a pressure test if there are cooling concerns, a workshop can confirm the cap’s rating.

There’s no strict kilometre-based replacement interval in Subaru literature for the cap, but many techs in Australia and New Zealand treat it as a small, preventative item: replace it if there are any symptoms, whenever the cooling system is serviced or hoses are renewed, or proactively around 5–7 years/100–150,000 km if it’s original. Always match the pressure rating on the OE cap (around 1.1 bar for the non-turbo XV) — going higher can stress hoses and the radiator, while lower can reduce the boiling margin.

Handy tip: when the engine’s completely cold, the top hose should feel normal (not sucked flat). A collapsed hose after cool-down can point to a cap that’s not venting correctly.

Popular questions about the 2016 Subaru XV radiator cap

Does the 2016 Subaru XV have a radiator cap and where is it?
Yes. It’s on the radiator filler neck, typically at the top tank near the upper hose. There’s also an overflow reservoir with a simple, non-pressurised lid — don’t mix the two up.

How often should the radiator cap be replaced?
There’s no fixed interval, but it should be inspected at every cooling system service. Many workshops replace a cap showing any seal damage, weak spring tension, failed pressure test, or as a preventative measure at roughly 5–7 years/100–150,000 km.

What pressure rating is correct for the XV’s radiator cap?
For the non-turbo 2.0L FB20, the correct rating is around 108 kPa (1.1 bar). Always match the original cap’s rating listed under the bonnet or in parts catalogues, using the wrong rating can create cooling issues.