2023 Ford F-250 Super Duty — Coolant Capacity & Type

The 2023 Ford F-250 Super Duty holds anywhere from 16.5 quarts (15.6 liters) for the 6.8L gas engine to a massive combined total of over 46 quarts (43.5 liters) across the primary and secondary cooling systems for the 6.7L Power Stroke diesel. Keeping this heavy-duty workhorse properly cooled is critical, especially if you are hauling heavy loads or towing over steep grades.

As an ASE-certified master technician, I’ve put together this quick reference guide to help you maintain your F-250’s cooling system with the right fluids and capacities.

Quick Answer

If you are topping off or flushing the cooling system on your 2023 Ford F-250, here is the essential information you need:

• Total Cooling System Capacity: 16.5 to 17.5 quarts (Gas engines); ~46.6 quarts combined (6.7L Diesel primary and secondary systems).
• OEM Coolant Spec: Motorcraft Yellow Antifreeze/Coolant. This is a P-OAT (Phosphated Organic Acid Technology) coolant meeting Ford specification WSS-M97B57-A1 (concentrate) or WSS-M97B57-A2 (pre-diluted).
• Mix Ratio: 50/50 pre-mix of Motorcraft Yellow and distilled water. You can mix up to 60/40 (coolant-to-water) for extreme cold weather down to -60°F.

Capacity by Engine Option

The 2023 model year introduced the new 6.8L gas V8 and the High-Output 6.7L Power Stroke, alongside the standard 7.3L gas and 6.7L diesel. Note that diesel models have two separate cooling systems (Primary for the engine, Secondary for the charge air cooler/EGR).

Always verify your specific capacity in your owner's manual, as dual alternators or specific tow packages can slightly alter capacity.

Flush Interval

• Normal Duty: Ford recommends the initial coolant replacement at 100,000 miles or 6 years, whichever comes first. After the initial flush, replace it every 50,000 miles or 3 years.
• Severe Duty: If you frequently tow heavy loads, idle extensively, or operate in dusty/off-road environments, check the coolant strength regularly and consider flushing at 60,000 miles to protect the water pump and EGR cooler.

How to Refill & Bleed

Properly bleeding the cooling system on modern Super Duty trucks, particularly the 6.7L Power Stroke, is absolutely critical. Air trapped in the secondary cooling system can lead to immediate turbo and charge-air cooler overheating.

1. Drain the System: Open the radiator petcock(s) at the bottom corner of the radiator(s). The diesel has two radiators and two separate drain points.
2. Vacuum Fill (Highly Recommended): For the 6.7L diesel, you must use a pneumatic vacuum cooling system filler (like an Airlift tool). Pull a vacuum on the system to ensure no air is trapped in the complex EGR and charge-air cooler passages, then let the vacuum draw the 50/50 Motorcraft Yellow mixture in.
3. Manual Bleed (Gas engines): If you don't have a vacuum tool for the 6.8L or 7.3L gas engines, fill the reservoir slowly to the MAX line. Leave the cap off.
4. Run the Engine: Start the engine and turn the heater on max heat/fan. Let the engine reach operating temperature until the thermostat opens.
5. Top Off: As the coolant level drops, add more 50/50 mix to keep it between the MIN and MAX lines. Once the level stabilizes and hot air blows from the vents, install the cap and test drive. Let it cool completely and check the cold fill level one last time.

Common Cooling System Issues

While the 2023 F-250 is still relatively new, it shares architecture with the previous generation. Here is what to watch out for as the miles pile up:

• Primary Radiator Leaks (6.7L Diesel): The plastic end tanks on the primary radiator are known to develop hairline cracks under the immense heat and pressure of heavy towing. Check for yellow crust around the crimps.
• Secondary Coolant Pump Failure: On diesel models, the electric pump for the secondary system can occasionally fail, causing elevated intake air temperatures and a check engine light.
• Water Pump Weeping: On the gas V8s, listen for a squeaking pulley or look for coolant weeping from the water pump weep hole behind the pulley as the truck approaches 100,000 miles.

Keeping your Super Duty properly cooled is the best way to ensure it lasts for years to come. If you're experiencing leaks, overheating, or simply need a professional vacuum-flush for your Power Stroke, don't leave it to chance. Find a trusted shop on Repairius.