Parts for your 2018 Nissan Serena-Radiator hose

2018 Nissan Serena radiator hose — what it does and how to look after it

Based on technical references, a radiator hose is absolutely relevant to the 2018 Nissan Serena. The Nissan C27 Serena Service Manual (Cooling System section) depicts upper and lower radiator hoses for MR20DD petrol S-HYBRID models and details coolant hose routing for e-POWER variants. Nissan’s Electronic Parts Catalogue (FAST) also lists the upper and lower radiator hoses and associated clamps for 2018 C27 Serena trims. So yes — the Serena uses radiator hoses, and they’re a key part of the cooling system.

On a 2018 Serena, the radiator hose carries coolant between the engine (and, on e-POWER, additional thermal components) and the radiator under the bonnet. It helps the engine stay in the sweet spot for temperature, so it runs smoothly, sips less fuel, and avoids costly overheating dramas. If a hose perishes or a clamp loosens, coolant can leak, leading to high temps and potential engine damage — not exactly anyone’s idea of a good arvo.

For servicing, it’s smart to inspect the radiator hoses at every oil service and before long trips. They should be firm but pliable, without cracks, glazing, swelling, or soft spots. Any oil contamination on the hose rubber is a red flag. Check for crusty deposits at the ends or around clamps — that’s often dried coolant from a weep. On e-POWER models, remember there are extra coolant loops, they use hoses too and deserve the same checks.

Replacement is sensible as preventive maintenance around the 8–10 year mark or if any defect is found earlier. When replacing, use quality hoses that match the Serena’s routing and diameter, fit new clamps if the originals are tired, and refill with the correct Nissan-approved long-life (blue) premixed coolant. Never crack the cap hot, wait for the engine to cool, and bleed the system properly to avoid air pockets. After fitting, run the engine up to temperature with the heater on, top up as needed, and recheck for seepage after a few kilometres.

A tidy cooling system keeps the Serena happy in Aussie and Kiwi conditions — from school runs to holiday kilometres — and a healthy set of hoses is cheap insurance against overheating.

• Watch for leaks, swelling, soft spots, or cracking
• Inspect at every service, replace hoses proactively by 8–10 years
• Use the correct Nissan long-life blue coolant and bleed air properly

Popular questions

Does the 2018 Serena e-POWER have radiator hoses too?
Yes. While e-POWER drives the wheels electrically, it still uses an engine as a generator and has liquid cooling circuits. The service manual diagrams show hoses for the engine and thermal management components, so regular hose checks apply to e-POWER as well.

How often should radiator hoses be replaced on a 2018 Serena?
There’s no single kilometre rule for all drivers, but inspecting every service and replacing at the first sign of ageing is best. As preventive maintenance, many workshops recommend renewing original hoses around 8–10 years, especially in hotter climates or high-kilometre vehicles.

What are the signs a Serena radiator hose needs attention?
Look for coolant smell, drips under the front, white or greenish crust near clamps, soft or swollen sections, surface cracking, or temperature spikes on the gauge. Any of these mean it’s time to book a cooling system check and likely replace the hose.