Parts for your 2020 Nissan Pathfinder-Radiator cap

2020 Nissan Pathfinder radiator cap — what it does and how to look after it

Yes, the 2020 Nissan Pathfinder uses a radiator cap. Technical sources including the Nissan Factory Service Manual for the R52-series (Cooling System, “CO” section) specify a testable radiator cap with an opening pressure around 1.1 bar (about 108 kPa). The Nissan Electronic Parts Catalogue for MY2020 Pathfinder also lists a serviceable radiator filler cap for the VQ35DE engine, and the Owner’s Manual cautions against opening the radiator cap when hot — all clear signs this model is fitted with one.

The radiator cap isn’t just a lid. It’s a pressure regulator that lets the cooling system run under pressure, lifting the coolant’s boiling point so the Pathfinder can tow, climb, and cruise in Aussie and Kiwi heat without boiling. It also has a vacuum valve that draws coolant back from the overflow bottle as the engine cools, keeping the system full and air-free for stable temps and a reliable heater.

As part of regular servicing under the bonnet, the cap deserves a quick check. Only inspect it when the engine is stone cold. Look for perished rubber seals, a sticky or weak spring, crusty deposits, or a damaged neck on the radiator. If available, a workshop can pressure-test the cap to the spec in the Nissan manual (approximately 1.1 bar). If it won’t hold pressure or won’t pull coolant back from the reservoir, replace it with an OE cap or a reputable equivalent that matches the correct pressure rating.

Many technicians recommend replacing the radiator cap every 3–5 years or when any fault is found, particularly if the vehicle tows, sees lots of motorway kilometres, or operates in hot climates. A fresh cap is inexpensive and helps protect the far pricier radiator, water pump, hoses, and head gaskets. When topping up, use the correct Nissan Long Life Blue (premix or mix with demineralised water as specified), and never open the cap when hot — use the reservoir for small level checks between services.

• Common hints the cap is tired: coolant loss into the overflow bottle without returning, collapsed hoses after cool-down, unexplained overheating at speed, or rusty/white crust on the cap seat.
• Fit the new cap squarely and tighten firmly by hand, no tools needed.

Does the 2020 Pathfinder have a radiator cap or just a reservoir?

It has a radiator cap. Nissan’s R52 Factory Service Manual lists a radiator cap with a specified relief pressure, and the EPC shows a dedicated filler cap for this model. The plastic bottle alongside the radiator is the overflow/reservoir, not the pressurised fill point.

What pressure rating should the radiator cap be?

The factory spec is approximately 1.1 bar (about 108 kPa). Always match the OE rating printed on the original cap or confirm against Nissan service data to maintain the correct boiling margin and hose protection.

How often should the radiator cap be replaced?

Have it inspected at each service and pressure-tested when the coolant is changed. In local conditions, many workshops suggest replacing the cap every 3–5 years, or immediately if it fails a pressure test or shows seal or spring damage.