Parts for your 2013 Holden Captiva 5-Radiator cap

Radiator cap on a 2013 Holden Captiva 5 — is it actually a thing?

Short answer: no traditional radiator cap lives on the radiator of a 2013 Holden Captiva 5. Technical references including the Holden Captiva CG Series II Owner’s Handbook (2013), GM Service Information for the Chevrolet Captiva Sport/Opel Antara platform, and GM/ACDelco parts catalogues all show a sealed cooling system that uses a pressurised coolant surge (expansion) tank with a pressure cap. There’s no filler neck or cap on the radiator itself, the only cap you’ll undo is on the plastic surge tank, typically rated around 140 kPa (about 20 psi), commonly listed under GM part families like 13227300 for this platform.

Why the change? Modern Holden/GM designs moved the pressure cap to a remote surge tank to lift the fill point above the engine, help separate air from coolant, and make bleeding simpler. It also improves packaging under the bonnet and reduces the chance of spills right over the radiator core. The system constantly routes a small flow back to the surge tank, purging air and keeping the coolant level honest without drivers needing to crack a cap on a hot radiator.

So, while parts sites might call it a “radiator cap”, on the Captiva 5 it’s the surge tank pressure cap doing the job. If the vehicle’s running hot, pushing coolant out, or the heater goes lukewarm under load, a weak cap could be part of the story. Only ever check or replace it when the engine is stone cold.

• What to look for: perished rubber seals, cracked or swollen plastic, coolant crust around the neck, or a sweet coolant smell after driving.
• Handy servicing tip: a cooling-system pressure tester with the correct adaptor can test cap holding pressure. If it won’t hold its rated kPa, bin it and fit a quality replacement.
• Fluids: stick with the specified long-life OAT coolant (Dex-Cool type) and don’t mix colours. After refilling, let the engine idle with the heater on, the surge tank system self-bleeds.

Bottom line for the Captiva 5 owner: there’s no separate radiator cap to service. The cap that matters is the pressure cap on the coolant surge tank, and keeping that bit healthy helps the whole cooling system stay on song.

Popular questions about the 2013 Holden Captiva 5 “radiator cap”

Does the 2013 Captiva 5 have a radiator cap on the radiator?
No. The cooling system is sealed and uses a pressurised surge (expansion) tank. The only cap you’ll remove is on that tank, not on the radiator. This layout is confirmed in the Holden owner’s handbook and GM service literature for the Captiva/Antara platform.

What pressure cap does a Captiva 5 use?
Most Captiva 5 models use a cap around 140 kPa (about 20 psi), printed on the cap itself. Always match the rating on your existing cap or check a Holden/GM parts catalogue for your VIN to be safe.

When should the surge tank cap be replaced?
If you see cracked seals, damaged plastic, coolant residue around the neck, or experience overheating and coolant loss with no obvious leaks, test or replace the cap. It’s a cheap part that can prevent bigger headaches.