Parts for your 2020 Ford Ranger-Radiator cap

2020 Ford Ranger radiator cap — what’s the go?

The 2020 Ford Ranger doesn’t use a traditional radiator cap on the radiator itself. Instead, it runs a sealed, pressurised cooling system with a remote expansion/degas bottle under the bonnet, and the only cap in play is on that bottle. That cap manages system pressure and coolant fill. Technical references back this up: the 2020 Ford Ranger Owner’s Manual directs checking and filling only at the coolant reservoir and warns not to remove the reservoir cap when hot, there’s no instruction to access a radiator neck. Ford’s Workshop Manual (Section 303-03, Engine Cooling) for the 2.3L EcoBoost and diesel variants also diagrams a pressurised degas bottle as the service point and pressure control device.

So while many people still say “radiator cap”, on this Ranger the function lives on the coolant expansion tank cap. It’s a safer, cleaner setup that keeps pressure control and filling in one spot away from the radiator core.

• Better air separation: The degas bottle helps purge trapped air, keeping coolant flow stable and reducing hot spots.
• Consistent pressure control: The reservoir cap holds a set pressure and vents/recovers fluid as the coolant expands and contracts.
• Packaging and safety: No cap on a hot radiator neck means less scald risk and more flexible cooling-pack layouts.
• Easier servicing: Coolant checks and top-ups happen in the reservoir, with clear min/max marks.

Servicing tips still matter. The expansion tank cap is a pressure device with seals and a relief valve, so it should be in good nick. Only open it when the engine is stone cold. If there’s dried coolant crust on the cap, cracked rubber, frequent low-coolant warnings, a sweet smell, or hoses that collapse after cool-down, the cap may not be holding pressure and should be replaced with an OE-spec, correct-pressure cap. There isn’t a set replacement interval in Ford’s schedule—treat it as condition-based. Use only the coolant specified in the Owner’s Manual, and keep the level between the marks, overfilling can cause overflow once the engine’s hot.

Technical sources referenced: Ford 2020 Ranger Owner’s Manual (Cooling/Engine Coolant sections—reservoir-only fill and safety cautions) and Ford Workshop Manual, Section 303-03 Engine Cooling (system layout with pressurised degas bottle and cap). These documents identify the expansion tank and cap as the sole service and pressure-control point, confirming there’s no separate radiator cap on the 2020 Ranger.

FAQs

Does a 2020 Ford Ranger have a radiator cap?
It doesn’t have a cap on the radiator neck. The pressure cap is on the coolant expansion/degas bottle and handles filling and pressure relief.

Where does coolant get topped up on a 2020 Ranger?
Only at the expansion tank. When the engine is completely cold, remove the reservoir cap, top up to the mark with the specified coolant, refit the cap firmly, and check for leaks.

How can someone tell if the coolant cap is failing?
Look for dried coolant around the cap, a recurring low-coolant message, a sweet smell after driving, or hoses that stay collapsed when cold. Any of these can point to a weak cap that’s not holding pressure.