2025 Ford F-350 Super Duty — A/C Refrigerant & Oil

Quick answer

• Refrigerant: R-1234yf (2025 Super Duty uses yf; Ford transitioned from R-134a to R-1234yf on most models starting mid-2010s. Always verify the underhood HVAC label.)
• Full system charge: commonly about 28–32 oz (800–900 g), varies by engine/cab and whether it’s pickup vs. chassis cab. Confirm the exact charge on the vehicle’s A/C specification decal.
• PAG oil: PAG 46 (R-1234yf-compatible). Total system oil is typically about 7–8 oz (210–240 mL) from the factory. When replacing parts, add oil per Ford WSM component amounts rather than guessing a total.
• Service port locations: Low-side port on the suction line near the accumulator/evaporator at the passenger-side firewall. High-side port on the liquid line near the condenser/front right of the radiator support. Exact routing can vary with engine and body style.

Why R-1234yf matters

R-1234yf is the low–global-warming-potential successor to R-134a. By 2025, the F-350 Super Duty uses yf, which:

• Lowers environmental impact compared to R-134a and helps meet EPA and global regulations.
• Costs more per ounce than R-134a, so charging precisely by weight is critical.
• Requires SAE J2843-certified recovery/recycle/recharge equipment and dedicated R-1234yf fittings, oils, and leak detection tools (SAE J2913). Do not attempt to retrofit fittings or mix refrigerants.
• Is classified A2L (mildly flammable). Follow shop safety protocols: no ignition sources, use proper ventilation, and rely on the correct recovery machine.

Recharge procedure (high-level)

1. Identify the refrigerant and charge spec on the underhood label. Most 2025 F-350s list R-1234yf with a specific weight in ounces/grams.
2. Recover any remaining refrigerant using an SAE J2843 R-1234yf machine. Venting is illegal.
3. Repair leaks before recharging. Replace any disturbed sealing washers/O-rings with R-1234yf-compatible parts. If the system was opened to atmosphere, replace the desiccant (on Super Duty, the condenser often incorporates the desiccant/drier—replace the condenser if required by Ford’s procedure).
4. Evacuate (vacuum) the system to remove air and moisture. Pull to deep vacuum and hold. Many techs target 30+ minutes of evacuation, then verify vacuum holds before charging.
5. Charge by weight only. Use the machine to meter the exact amount shown on the label. Do not charge by pressures or temperature alone, and avoid top-off can methods—especially with yf.
6. Verify operation: condenser fan/clutch engagement, center vent temps, and line temperatures. Use a scan tool to check HVAC and PCM data PIDs for commanded compressor displacement, fan control, and ambient inputs if cooling is marginal.

Oil note: Do not guess at total oil. When individual components are replaced, add the Ford Workshop Manual (WSM 412-00) specified oil amount for that component and drain/measure the old compressor if required by the procedure. Use only R-1234yf-compatible PAG 46 or the Motorcraft-specified equivalent.

Common A/C problems for this vehicle

• Condenser damage/leaks: The front-mounted condenser/drier is exposed to road debris. A leak here is common. Because the drier is integrated, replacement of the condenser is typically required if the drier is saturated or the system has been open.
• Compressor control/insufficient cooling at idle: The variable-displacement compressor depends on correct charge and airflow. Cooling complaints at idle can be due to low charge, condenser airflow restrictions (bug screens, debris), a weak fan clutch/e-fan issue, or a sticking control valve inside the compressor.
• Orifice tube restrictions: The fixed orifice tube can clog with debris after a compressor failure, causing low suction/low discharge and poor cooling. Inspect and replace the orifice tube and thoroughly flush lines/evaporator (as applicable) after any internal failure.
• Evaporator core or line O-ring leaks: Less common but possible. Look for trace dye and use an SAE J2913-compliant electronic leak detector around the case seams and drain.
• Blend/temperature door actuator faults: Not a refrigerant issue, but can mimic A/C problems with uneven or warm air. HVAC self-tests via scan tool can identify actuator DTCs.

OEM service info highlights

• Refer to Ford Workshop Manual, Section 412-00 (Climate Control System), for model-specific capacities, oil distribution amounts, evacuation, and charge steps.
• Always charge by the exact weight on the underhood label for that VIN. Super Duty capacities vary by engine (gas vs. Power Stroke) and body (pickup vs. chassis cab).
• Use R-1234yf-specific service equipment (SAE J2843), leak detection (J2913), and recovery cylinders. Do not intermix yf and 134a equipment.
• Replace sealing washers/O-rings any time a joint is opened; lubricate seals with the same PAG oil used in the system. Observe torque specs from the WSM.

When to call a pro

• You don’t have an R-1234yf recovery machine or scale to charge by weight.
• The system won’t hold vacuum, or you suspect internal contamination/compressor failure.
• Repeated cooling complaints at idle, or abnormal high-side pressures suggesting airflow or control issues.
• You’re unsure of the correct oil distribution when replacing multiple components.

Safety disclaimer: Servicing mobile A/C requires EPA Section 609 certification to purchase/handle refrigerant. R-1234yf is mildly flammable—work in a well-ventilated area away from sparks/open flames, wear eye/hand protection, and use only approved recovery/recharge equipment. Never use compressed air or oxygen for pressure testing.

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