2018 Ford F-250 Super Duty Coolant Capacity & Type

The 2018 Ford F-250 Super Duty coolant capacity varies by engine, but generally holds between 18 and 24 quarts (17-22.7 liters) of coolant.

Quick Answer

• Total Cooling System Capacity:
  • 6.2L V8: Approximately 18.5 quarts (17.5 liters)
  • 6.7L Power Stroke Diesel: Approximately 24 quarts (22.7 liters)
• OEM Coolant Spec: Ford's Motorcraft Orange Antifreeze/Coolant, meeting Ford Specification WSS-M97B44-D. This is an Organic Acid Technology (OAT) coolant.
• Mix Ratio: Typically a 50/50 mix of coolant concentrate and distilled water. Pre-mixed 50/50 solutions are also available and recommended for convenience and accuracy.

Capacity by Engine Option

The 2018 Ford F-250 Super Duty was offered with two primary engine options, each with a different cooling system capacity:

Flush Interval

Ford recommends the following coolant flush intervals for the 2018 F-250 Super Duty with Motorcraft Orange coolant:

• Normal Duty: Replace initially at 100,000 miles (160,000 km) or 6 years, then every 50,000 miles (80,000 km) or 3 years thereafter.
• Severe Duty (e.g., heavy towing, off-road use, extreme temperatures): It's advisable to inspect the coolant annually and consider shorter flush intervals, potentially every 50,000 miles (80,000 km) or 3 years from the initial fill.

How to Refill & Bleed

Refilling and bleeding the cooling system on a 2018 Ford F-250 Super Duty is a critical step to ensure proper cooling and prevent air pockets. Always perform this on a cool engine.

1. Drain: With the engine cool, place a drain pan under the radiator and open the petcock (drain valve) on the bottom of the radiator. For a complete flush, you may also need to drain from engine block drains, if equipped and accessible.
2. Rinse (Optional but Recommended): After draining, close the petcock and fill the system with distilled water. Run the engine with the heater on until it reaches operating temperature (thermostat opens), then drain again. Repeat until the water runs clear. Do NOT use tap water for rinsing or filling.
3. Fill: Close all drain points. Slowly add the specified Motorcraft Orange 50/50 coolant mix to the coolant reservoir (degas bottle) until it reaches the MAX fill line. Do not overfill.
4. Bleed Air:
   • Start the engine and let it idle with the heater on high (full hot, fan on low). This helps circulate coolant through the heater core.
   • Keep the cap off the degas bottle and observe the coolant level. As the engine warms up, the thermostat will open, and the coolant level may drop. Add more coolant as needed to maintain the MAX line.
   • Gently squeeze the upper and lower radiator hoses to help dislodge any trapped air bubbles.
   • Allow the engine to run until it reaches normal operating temperature and the cooling fan cycles on and off at least twice. This ensures the thermostat has opened fully.
   • Watch for steady streams of coolant returning to the degas bottle, indicating circulation. Revving the engine gently (to about 2000-2500 RPM for short bursts) can help expel air.
   • Some F-250 models, particularly the 6.7L Power Stroke, can be prone to air pockets. A vacuum filler tool is highly recommended for these vehicles to ensure a complete fill and minimize air entrapment.
5. Final Check: Once the engine is cool again, recheck the coolant level in the degas bottle and adjust if necessary. Keep an eye on the coolant level over the next few drive cycles.

Common Cooling System Issues

Owners of 2018 Ford F-250 Super Duty trucks may encounter some common cooling system issues, especially with higher mileage or improper maintenance:

• Water Pump Leaks: A common wear item, especially on the 6.2L V8. Look for coolant stains or drips near the front of the engine.
• Radiator Leaks: Over time, plastic end tanks or aluminum cores can develop leaks due to age, vibration, or impact.
• Degas Bottle (Coolant Reservoir) Cracking: The plastic reservoir can become brittle and crack, leading to coolant loss. This is more prevalent in older vehicles, but worth noting.
• Thermostat Failure: A stuck-open thermostat can cause the engine to run too cool, leading to inefficient operation. A stuck-closed thermostat can lead to overheating.
• EGR Cooler Issues (6.7L Power Stroke Diesel): The exhaust gas recirculation (EGR) cooler on the 6.7L Power Stroke can be prone to internal leaks, allowing coolant to enter the exhaust system or combusion, leading to coolant loss without external leaks. White smoke from the exhaust can be a symptom.
• Coolant Contamination/Sludge: Mixing incompatible coolants (e.g., OAT with traditional green IAT) can lead to gel formation, corrosion, and severe cooling system blockages. Always use the specified Motorcraft Orange coolant.

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