Parts for your 2018 Toyota Land cruiser-Radiator cap

2018 Toyota Land Cruiser radiator-cap: what it does, where it is, and when to replace it

Technical sources confirm the 2018 Toyota Land Cruiser uses a pressurised radiator cap. The Toyota Electronic Parts Catalogue (EPC) lists a “Cap Sub‑Assembly, Radiator” for both URJ200 (5.7L petrol) and VDJ200 (4.5L diesel) variants, and the Toyota Repair Manual cooling system section details pressure testing of the radiator cap as part of standard service checks. That means a radiator-cap is fitted and relevant on the 2018 Land Cruiser.

On this generation Land Cruiser, the radiator-cap is a pressure cap that seals the cooling system and regulates pressure. By holding a set pressure (typically around 1.1 bar/108 kPa — check the rating stamped on the cap), it raises the coolant’s boiling point so the V8 stays happy towing, climbing dunes, or hauling the family and gear across town. It also manages coolant flow to and from the overflow/expansion bottle as the engine heats and cools, keeping air out and coolant volume stable.

Because it’s a small part doing a big job, a tired cap can cause hard-to-pinpoint dramas: slow coolant loss, overheating under load, soft or collapsing hoses, or a heater that goes cold at idle. A good cap maintains pressure, a dodgy one vents too soon, won’t hold pressure on a tester, or has a perished seal.

As part of regular servicing on a 2018 Land Cruiser, workshops typically:

• Inspect the cap cold: check the rubber seals, spring action, and neck fit.
• Pressure-test the cap to its stamped rating with a cap tester.
• Replace the cap if it fails the test, shows cracked or flattened seals, corrosion, or if there’s evidence of overflow bottle burping under normal temps.

There’s no fixed replacement interval from Toyota for the cap itself, but many techs treat it as a consumable: if the vehicle works hard (towing, off-road, high-heat environments) or when chasing cooling complaints, a fresh, genuine or OE-spec cap matched to the correct kPa rating is cheap insurance. When coolant is renewed (Toyota Super Long Life Coolant intervals apply), it’s a good moment to test the cap. Always remove the cap only when the engine is stone cold, under the bonnet of a Land Cruiser there’s plenty of heat-soak, and a hot system can release scalding pressure if opened early.

Location-wise, expect the pressure cap on the radiator neck or on a pressurised surge tank near the top hose area, depending on engine variant. Either way, it’s designed to be the system’s pressure point—so matching the correct cap style and rating to the VIN is key.

Popular questions about the 2018 Toyota Land Cruiser radiator-cap

What pressure rating should the radiator-cap be on a 2018 Land Cruiser?
Most 200 Series caps are around 108 kPa (1.1 bar), but the definitive answer is stamped on the cap itself and verified by the VIN in the Toyota parts catalogue. Using the correct rating ensures the coolant’s boiling point and hose loads stay within design limits.

Where is the radiator-cap located on the 2018 Land Cruiser?
It’s typically on the radiator filler neck or on a pressurised surge/degassing tank near the top radiator hose. The exact spot varies between the 5.7L petrol and 4.5L diesel layouts, but it will be the only cap with a pressure warning label. Always check placement by VIN in the service literature if unsure.

What are the signs a radiator-cap needs replacing?
Look for crusty coolant stains around the cap, a sweet smell under the bonnet, hoses that suck flat after cool-down, rising temps when towing, or coolant being pushed into the overflow bottle and not returning. A cap that fails a pressure test or has cracked, hardened, or flattened seals should be replaced.