2021 Ford Explorer Coolant Capacity & Type Guide

The 2021 Ford Explorer holds between 11.2 and 14.8 quarts (10.6 to 14.0 liters) of coolant, depending on the specific engine and whether the vehicle is equipped with an auxiliary rear heater or heavy-duty towing package. As an ASE-certified master technician, I regularly service the newer CD6-platform Explorers, and maintaining the correct fluid levels and using the precise OEM coolant chemistry is absolutely critical for the longevity of your EcoBoost or Hybrid engine.

Below is your comprehensive guide to the 2021 Ford Explorer's cooling system.

Quick answer

• Total Cooling System Capacity: 11.2 to 14.8 quarts (10.6 to 14.0 liters)
• OEM Coolant Spec: Motorcraft Yellow Antifreeze/Coolant. Ford specification WSS-M97B57-A1 (concentrate) or WSS-M97B57-A2 (prediluted). This is a P-OAT (Phosphated Organic Acid Technology) coolant. Do not mix with the older Motorcraft Orange.
• Mix Ratio: 50/50 mixture of coolant concentrate and distilled water, or simply use 50/50 pre-mixed coolant out of the bottle.

Capacity by engine option

Because the 2021 Explorer offers several different powertrains—ranging from the efficient 2.3L inline-four to the high-performance 3.0L V6 in the ST—the total fluid capacity varies. Vehicles with rear climate control systems (rear heater core) also require more fluid.

(Note: The Hybrid model also features a separate low-temperature cooling loop for the hybrid inverter system, which has its own dedicated capacity and reservoir.)

Flush interval

Keeping your engine operating at the proper temperature requires fresh coolant. Over time, the protective additives in the P-OAT coolant break down, which can lead to corrosion or electrolysis inside the aluminum engine block.

• Normal Duty: Ford recommends the initial coolant replacement at 100,000 miles or 5 years, whichever comes first. After the initial flush, the interval drops to every 50,000 miles or 3 years.
• Severe Duty: If you frequently tow heavy loads, idle extensively (such as police interceptor duty), or drive in extreme off-road/dusty environments, you should perform your first coolant flush at 60,000 miles.

How to refill & bleed

The 2.3L and 3.0L EcoBoost engines utilize complex cooling routes to manage temperatures for both the engine block and the turbochargers. Trapped air can cause localized boiling, leading to catastrophic turbo or engine failure.

1. Prep the Vehicle: Ensure the engine is completely cold. Locate the radiator drain petcock on the lower side of the radiator and drain the old fluid into a suitable pan.
2. Use a Vacuum Filler: For the 2020+ Ford Explorer generation, using a vacuum filling tool (like an Airlift) is highly recommended. Pull a vacuum on the empty system via the degas bottle (coolant reservoir).
3. Refill: Once a vacuum is held (which also tests the system for leaks), draw the 50/50 mixed Motorcraft Yellow coolant into the system. This method prevents air pockets from forming in the turbo coolant lines and the complex rear heater core lines.
4. Final Bleed: If you do not have a vacuum filler, you must fill the degas bottle slowly, run the engine with the heater on maximum heat, and hold RPMs around 2,500 for a few minutes. Check the fluid level repeatedly after the engine cools. Top off the degas bottle to the MAX line.

Common cooling system issues

While the 2020+ CD6 rear-wheel-drive platform solved the dreaded internal water pump failures found on the older transverse 3.5L V6s, the 2021 generation has a few quirks to watch out for:

• Turbo Coolant Line Leaks: The quick-connect fittings on the coolant lines feeding the turbochargers (especially on the 3.0L EcoBoost) can degrade over time due to extreme heat cycles, resulting in slow coolant leaks.
• Thermostat Housing Seepage: The plastic thermostat housings can occasionally warp or crack, leading to a loss of pressure and coolant.
• Degas Bottle Cracks: Keep an eye on the pressurized coolant reservoir. Hairline cracks along the plastic seams can cause the system to lose pressure, lowering the boiling point of the fluid.

If you suspect a leak or need a professional coolant exchange to protect your EcoBoost's turbochargers, do not put it off. Find a trusted shop on Repairius.