Parts for your 2013 Toyota Hilux-Radiator cap

2013 Toyota Hilux Radiator Cap

Yes — the 2013 Toyota Hilux uses a pressurised radiator cap mounted on the radiator, not just a sealed overflow bottle. This is documented in Toyota service literature and parts catalogues for KUN/GGN series Hilux (2005–2015), which specify a “Cap Sub-Assembly, Radiator” with a nominal pressure rating around 108 kPa (1.1 bar). The Hilux owner’s manual for this era also cautions against removing the radiator cap when hot and outlines coolant checks at the radiator filler neck, confirming the cap’s presence and role.

• Toyota Hilux Owner’s Manual (2011–2015 AUS/NZ): Cooling system section references the radiator cap and safe removal.
• Toyota Repair Manual (1KD-FTV/1GR-FE Cooling): “Radiator Cap: Inspect cap sub-assembly, standard opening pressure approx. 108 kPa (1.1 bar).”
• Toyota Electronic Parts Catalogue (KUN26R/GGN25R, 2011–2015): Radiator cap listed as “Cap Sub-Assy, Radiator,” commonly 16401-31xxx series.

On a 2013 Hilux, the radiator cap does more than just seal the top of the radiator — it sets the system’s pressure so the coolant can run hotter without boiling, helps purge air, and draws coolant back from the overflow as things cool down. If the cap’s spring or seals are tired, the ute can overheat earlier than it should, lose coolant into the bottle, or end up with soft top hoses and crusty deposits around the filler neck.

For hassle-free touring and towing, it’s worth treating the cap as a service item. Stick with the correct rating (typically 108 kPa/1.1 bar for Hilux of this vintage) and a quality cap that matches the radiator neck profile. Check the rubber seals for nicks, hardening, or swelling each service, and replace the cap every 5 years or 100,000 km — sooner if there are any signs of overheating, random coolant loss, or if the system’s been opened for radiator, water pump, or hose work.

Good habits under the bonnet:

• Only remove the radiator cap when the engine is stone cold. Use a rag and crack it slowly to release any residual pressure.
• Inspect for white/pink crust (dried coolant), perished seals, and a weak spring. A cooling-system pressure tester can check the cap opens at the right pressure.
• After refilling with Toyota Super Long Life Coolant (red/pink), bleed the system properly and confirm the overflow hose between the neck and bottle is tight and crack-free.
• If upgrading radiators, match the cap rating to Toyota spec — don’t “go higher” to mask problems, fix the root cause.

Popular questions about the 2013 Toyota Hilux radiator cap

Does a 2013 Hilux have a radiator cap or only an expansion tank?
It has a proper pressurised radiator cap on the radiator itself, plus a non-pressurised overflow bottle. Coolant level checks are done at both the radiator (when cold) and the bottle.

What pressure cap should a 2013 Hilux use?
Toyota specifies roughly 108 kPa (1.1 bar) for this generation. Keep to the factory rating noted in the owner’s manual or under-bonnet label for reliable warm-up and boil-over protection.

How often should the radiator cap be replaced?
Inspect at every service. Replace every 5 years/100,000 km, or immediately if there’s coolant crust, perished rubber, unexplained coolant loss, or overheating under load.