2025 Ford F-350 Super Duty Fluid Type Specs

Quick Reference

Fluid	Type/Spec	Capacity
Engine Oil (6.7L Diesel)	SAE 5W-40, WSS-M2C171-F1 (API CK-4)	~13 quarts (verify in owner's manual)
Engine Oil (7.3L Gasoline)	SAE 6W-30, WSS-M2C961-A1 (API SP/ILSAC GF-6A)	~7.5 quarts (verify in owner's manual)
Engine Coolant	Motorcraft Orange Prediluted Antifreeze/Coolant, WSS-M97B44-D2	~28 quarts (diesel), ~19 quarts (gasoline) (verify in owner's manual)
Transmission Fluid (10R140)	MERCON LV ULV (Ultra Low Viscosity)	~19 quarts (dry fill, verify in owner's manual)
Transfer Case (BW 1356 series)	MERCON LV ULV	~2 quarts (verify in owner's manual)
Front Differential (M275 series)	SAE 75W-85 Synthetic Hypoid Gear Lubricant (M275) / SAE 75W-90 Synthetic Hypoid Gear Lubricant (Dana M300)	~2.9-3.3 quarts (M275), ~3.7 quarts (Dana M300) (verify in owner's manual)
Rear Differential (S110 series)	SAE 75W-140 Synthetic Hypoid Gear Lubricant (Ford S110)	~4 quarts (Ford S110) (verify in owner's manual)
Rear Differential (Dana M300)	SAE 75W-90 Synthetic Hypoid Gear Lubricant (Dana M300)	~3.9 quarts (Dana M300) (verify in owner's manual)
Brake Fluid	Motorcraft DOT 4 Low Viscosity (LV) Brake Fluid, WSS-M6C65-A2	As needed (verify in owner's manual)
Power Steering Fluid	MERCON ULV	As needed (verify in owner's manual)
Washer Fluid	Motorcraft Premium Windshield Washer Concentrate	~1 gallon (verify in owner's manual)
DEF (Diesel)	API CK-4 / ISO 22241	~7-9 gallons (verify in owner's manual)

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Engine Oil

The 2025 Ford F-350 Super Duty offers two primary engine choices: the 6.7L Power Stroke V8 Turbo Diesel and the 7.3L Godzilla V8 Gasoline engine. Each engine has specific oil requirements.

For the 6.7L Power Stroke V8 Turbo Diesel engine, Ford specifies SAE 5W-40 engine oil meeting Ford specification WSS-M2C171-F1. This specification aligns with API CK-4 standards, designed for high-performance diesel engines with exhaust aftertreatment systems. Using oil that does not meet WSS-M2C171-F1 can lead to premature wear of engine components and potential issues with the diesel particulate filter (DPF) and other emissions equipment. The capacity for the 6.7L diesel is approximately 13 quarts; however, always verify the exact capacity in your owner's manual as it can vary slightly with filter changes.

For the 7.3L Godzilla V8 Gasoline engine, Ford recommends SAE 6W-30 engine oil meeting Ford specification WSS-M2C961-A1. This specification corresponds to API SP and ILSAC GF-6A standards, indicating a fuel-efficient multigrade engine oil providing protection against low-speed pre-ignition (LSPI), timing chain wear, and turbocharger protection. Using an oil that doesn't meet this specification can compromise engine longevity and fuel efficiency. The capacity for the 7.3L gasoline engine is approximately 7.5 quarts; always confirm the precise amount in your owner's manual.

Intervals and Pitfalls: Ford generally recommends oil change intervals of 7,500 to 10,000 miles or every six to twelve months, whichever comes first, under normal driving conditions. However, severe duty cycles (towing heavy loads, extreme temperatures, dusty conditions) may necessitate more frequent changes. Always refer to your owner's manual for the precise maintenance schedule. Never mix different oil viscosities or types (conventional, synthetic blend, full synthetic) unless explicitly stated by Ford, and always ensure the oil meets the specified Ford WSS-M2C and API standards.

Engine Coolant

The 2025 Ford F-350 Super Duty utilizes Motorcraft Orange Prediluted Antifreeze/Coolant, which meets Ford specification WSS-M97B44-D2. This is an Organic Acid Technology (OAT) coolant, easily identifiable by its orange color. It provides long-life corrosion protection for aluminum and other metal components within the cooling system. It is critical to use only this specified coolant. Mixing OAT coolants with different chemistries, such as Hybrid Organic Acid Technology (HOAT) or Inorganic Acid Technology (IAT) coolants, can lead to chemical reactions, gel formation, reduced cooling efficiency, and severe damage to the cooling system and engine.

The capacity for the diesel engine is roughly 28 quarts, while the gasoline engine holds approximately 19 quarts. These are general figures; consult your owner's manual for exact capacities.

Intervals and Pitfalls: Ford typically recommends a coolant flush and fill every 100,000 miles or five years, whichever comes first. However, inspect the coolant level and condition regularly. Never use tap water for diluting concentrated coolant (if applicable), always use distilled water to prevent mineral deposits. Always ensure the system is properly bled of air after any coolant service.

Transmission Fluid

All 2025 Ford F-350 Super Duty trucks equipped with the 10-speed automatic transmission (10R140) utilize MERCON ULV (Ultra Low Viscosity) automatic transmission fluid. It is crucial to use only MERCON ULV, as this transmission is designed with very tight tolerances and specific friction material compatibility that only this fluid can provide. Using any other type of automatic transmission fluid, such as MERCON LV, MERCON V, or universal ATFs, can lead to premature transmission wear, shuddering, poor shift quality, and ultimately transmission failure. The exact Ford specification for MERCON ULV is not always publicly listed as a WSS-M number, but adherence to the MERCON ULV standard is paramount.

The dry fill capacity for the 10R140 transmission is around 19 quarts. Note that a drain and fill will typically only replace a portion of the fluid. A full flush usually requires specialized equipment. Always verify the exact capacity in your owner's manual.

Intervals and Pitfalls: Ford generally recommends inspecting the transmission fluid level and condition at regular service intervals. For severe duty (towing, commercial use), more frequent fluid changes may be necessary, often around 30,000 to 60,000 miles. For normal use, the interval can extend up to 150,000 miles, but always consult your owner's manual. Never overfill the transmission, and always use the correct fluid type.

Transfer Case

For 4WD/AWD equipped 2025 Ford F-350 Super Duty models (likely utilizing a BorgWarner 1356 series or similar transfer case), the specified fluid is also MERCON ULV. This matches the requirement for the 10R140 automatic transmission, simplifying fluid inventory for some. Like the transmission, using any other fluid can cause serious damage to the transfer case components due to incorrect friction characteristics.

The capacity for the transfer case is approximately 2 quarts, but this can vary slightly based on the specific transfer case model. Always consult your owner's manual.

Intervals and Pitfalls: Transfer case fluid should typically be inspected and possibly changed at intervals similar to rear differential fluid, especially under heavy usage. Refer to your owner's manual for specific service intervals.

Front Differential

The front differential in the 2025 Ford F-350 Super Duty may vary depending on the axle manufacturer and specifications. For trucks equipped with the Ford M275 series front differential, the specified fluid is SAE 75W-85 Synthetic Hypoid Gear Lubricant (Ford WSS-M2C924-A). If your F-350 is equipped with certain heavy-duty Dana M300 series front axles, the specification may be SAE 75W-90 Synthetic Hypoid Gear Lubricant. It is critical to confirm the exact axle installed in your vehicle and the corresponding fluid specification from your owner's manual or OEM service information. Some differentials may require a friction modifier if they are limited-slip, though most heavy-duty truck front differentials are open.

The capacity for the M275 front differential generally ranges from 2.9 to 3.3 quarts. For Dana M300 axles, it can be around 3.7 quarts. Always verify the exact capacity in your owner's manual.

Intervals and Pitfalls: Front differential fluid changes are typically recommended less frequently than rear differentials, often every 60,000 to 100,000 miles for normal use, and more frequently for severe duty. Ensure the proper weight and type of synthetic gear lubricant is used. Check the vent tube for obstructions during service.

Rear Differential

Similar to the front differential, the rear differential fluid depends on the specific axle. For the heavy-duty Ford S110 series rear differential, the specified fluid is SAE 75W-140 Synthetic Hypoid Gear Lubricant (Ford WSS-M2C200-E). This heavy-duty fluid is designed for high loads and temperatures. If your F-350 is equipped with a Dana M300 series rear axle, it may require SAE 75W-90 Synthetic Hypoid Gear Lubricant. Some versions of these axles may be equipped with a limited-slip differential (LSD), in which case a friction modifier additive will be required in addition to the specified gear oil, or a gear oil that already contains the friction modifier. Always verify your specific axle type and whether it is an LSD.

The capacity for the Ford S110 rear differential is approximately 4 quarts. For Dana M300 rear axles, it can be around 3.9 quarts. These are estimates; always refer to your owner's manual for precise capacities.

Intervals and Pitfalls: Rear differential fluid usually requires changes more frequently than front differentials, especially if towing or hauling heavy loads. Intervals can range from 30,000 miles for severe service up to 100,000 miles for normal use. Always check for the presence of a limited-slip differential and add the correct friction modifier if needed. Ensure fill and drain plugs are properly torqued.

Brake Fluid

For the 2025 Ford F-350 Super Duty, Ford specifies Motorcraft DOT 4 Low Viscosity (LV) Brake Fluid meeting Ford specification WSS-M6C65-A2. It is crucial to use a DOT 4 LV fluid, as modern ABS and stability control systems are designed to operate with this lower viscosity fluid, especially in cold temperatures. While DOT 3 and standard DOT 4 fluids are hygroscopic (absorb moisture), standard DOT 4 typically has a higher boiling point than DOT 3. The "LV" designation is very important for proper system operation. Never use DOT 5 fluid, as it is silicone-based and incompatible with standard DOT 3/4/5.1 systems.

Intervals and Pitfalls: Brake fluid is hygroscopic, meaning it absorbs moisture over time, which lowers its boiling point and can lead to internal corrosion. Ford typically recommends changing the brake fluid every two years regardless of mileage. Always use fresh fluid from a sealed container. Do not leave the master cylinder cap off for extended periods, and thoroughly bleed the system to remove all air after service.

Power Steering Fluid

With the prevalence of electric power steering systems in modern trucks, traditional hydraulic power steering is becoming less common. However, if your 2025 F-350 Super Duty is equipped with a hydraulic power steering system, it will likely require MERCON ULV fluid, consistent with the transmission and transfer case. Always check your owner's manual to confirm the presence of a hydraulic system and the specific fluid type.

Intervals and Pitfalls: Power steering fluid generally has a long service life, but under severe conditions (heavy plowing, consistent maximum steering input), it may require more frequent inspection and possibly replacement. Check for leaks and ensure the fluid level is within the marked range on the reservoir.

Washer Fluid

Ford recommends Motorcraft Premium Windshield Washer Concentrate or an equivalent high-quality, all-season windshield washer fluid. Ensure the fluid offers freeze protection appropriate for your climate to prevent lines and reservoirs from freezing and bursting. Many aftermarket washer fluids contain detergents and anti-freeze agents that are suitable.

Intervals and Pitfalls: Top off as needed. Using plain water in freezing temperatures can damage the washer system. Avoid using household cleaners, as they can damage paint or plastic components.

Diesel Exhaust Fluid (DEF)

For 2025 F-350 Super Duty diesel models, Diesel Exhaust Fluid (DEF) is essential for the selective catalytic reduction (SCR) system, which reduces NOx emissions. The DEF must meet API CK-4 or ISO 22241 specifications. DEF is a non-toxic solution of 32.5% high-purity urea and 67.5% deionized water. It is crucial to use only certified DEF; using other liquids or contaminated DEF will damage the SCR system and lead to costly repairs.

The DEF tank capacity is typically around 7 to 9 gallons, but always check your owner's manual for the exact capacity.

Intervals and Pitfalls: DEF consumption is typically around 1-3% of fuel consumption. The vehicle's instrument cluster will provide warnings when the DEF level is low. Always store DEF in a cool, dry place away from direct sunlight. DEF has a shelf life, typically around 1-2 years, so check the expiration date. Do not allow DEF to freeze, although it will thaw back to its original state. Once it freezes, ensure it is completely thawed before use. Never put DEF in the fuel tank, or diesel into the DEF tank.

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