2018 Ford F-250 Super Duty Fluid Type Specifications

Quick Reference

Fluid	Type/Spec	Capacity
Engine Oil (6.2L)	SAE 5W-30, WSS-M2C946-B1 (API SN PLUS or newer)	7.0 quarts (6.6 liters) with filter
Engine Oil (6.7L)	SAE 10W-30, WSS-M2C171-F1 (API CK-4 or CJ-4)	13.0 quarts (12.3 liters) with filter
Engine Coolant	Ford Orange/Yellow VC-3-B, WSS-M97B44-D/WSS-M97B51-A1	18.2-19.1 quarts (17.2-18.0 liters) - verify in owner's manual for exact
Transmission (6R140)	MERCON LV automatic transmission fluid	17.5 quarts (16.6 liters) for overhaul
Transfer Case (BW 44-66)	MERCON LV automatic transmission fluid	2.0 quarts (1.9 liters)
Front Differential (Dana M275/M300)	SAE 80W-90 High Performance Gear Oil (XY-80W90-QL) or SAE 75W-85 Synthetic Hypoid Gear Lubricant (XO-75W85-QL) for M300	3.0-3.2 quarts (2.8-3.0 liters) - Dana M275, approx. 4.0 quarts (3.8 liters) - Dana M300
Rear Differential (Dana M275/M300)	SAE 75W-140 High Performance Synthetic Rear Axle Lubricant (XY-75W140-QL) with friction modifier if LSD	3.5-4.0 quarts (3.3-3.8 liters) - Dana M275, approx. 4.0 quarts (3.8 liters) - Dana M300
Brake Fluid	DOT 4 Low Viscosity (LV) Motor Vehicle Brake Fluid, WSS-M6C65-A2	Consult owner's manual
Power Steering Fluid	MERCON ULV or MERCON LV (check cap/manual)	Consult owner's manual
Washer Fluid	Ford Premium Windshield Washer Concentrate (ZC-32-A) or equivalent	1 gallon (3.8 liters)
DEF (6.7L Diesel)	Motorcraft Diesel Exhaust Fluid (PM-27-J) or equivalent, API certified ISO 22241	7.5 U.S. gallons (28.4 liters)

Engine Oil

The 2018 Ford F-250 Super Duty was available with two primary engine options: the 6.2L V8 gasoline engine and the 6.7L Power Stroke V8 diesel engine. Each requires a distinct engine oil type and specification.

For the 6.2L V8 gasoline engine, Ford specifies SAE 5W-30 engine oil meeting Ford specification WSS-M2C946-B1. This specification generally aligns with API SN PLUS or newer classifications, designed to protect against low-speed pre-ignition (LSPI) in turbocharged gasoline direct injection engines, although the 6.2L is naturally aspirated. The oil capacity for the 6.2L engine is approximately 7.0 quarts (6.6 liters) with a filter change. It is crucial to use oil that explicitly states it meets Ford WSS-M2C946-B1 to ensure proper engine lubrication and longevity. Oil change intervals are typically 7,500 to 10,000 miles or every 6-12 months, depending on driving conditions, as outlined in your owner's manual.

For the 6.7L Power Stroke V8 diesel engine, Ford requires SAE 10W-30 engine oil that meets the Ford specification WSS-M2C171-F1. This specification corresponds to API CK-4 or CJ-4 motor oil, designed for modern diesel engines with exhaust aftertreatment systems. The oil capacity for the 6.7L engine is substantial, at approximately 13.0 quarts (12.3 liters) with a filter change. Using the correct API CK-4/CJ-4 oil is vital for the proper function and longevity of the emission control systems, including the Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR). Adhere to the severe or normal duty oil change intervals specified in your owner's manual, generally ranging from 5,000 to 10,000 miles or every 6 months.

Engine Coolant

The 2018 Ford F-250 Super Duty utilizes an orange/yellow colored Motorcraft Orange Antifreeze/Coolant Concentrate (VC-3-B), which meets Ford specification WSS-M97B44-D or WSS-M97B51-A1 (for Pre-Diluted). This is a long-life, OAT (Organic Acid Technology) coolant. It is critical NOT to mix different types of coolants (e.g., OAT with HOAT or IAT), as this can lead to chemical reactions, gel formation, and severe damage to the cooling system components. Always use a coolant that explicitly states it meets Ford's WSS-M97B44-D specification. The cooling system capacity can vary slightly but is generally in the range of 18.2 to 19.1 quarts (17.2 to 18.0 liters). Always verify the exact capacity in your owner's manual or OEM service information. Coolant replacement intervals are typically very long, often 100,000 miles or more, but it's wise to check the system periodically for level and condition.

Transmission Fluid

The 2018 F-250 Super Duty with the TorqShift-G 6R140 automatic transmission requires MERCON LV automatic transmission fluid. Universal ATFs should never be used. Using anything other than MERCON LV can lead to erratic shifting, premature wear, and costly transmission damage. The total dry fill capacity for an overhaul is approximately 17.5 quarts (16.6 liters). A pan drop and filter change will replace significantly less fluid. Refer to your owner's manual for proper checking procedures and service intervals, which can vary based on usage and may include a severe duty schedule.

Transfer Case

For models equipped with four-wheel drive, the BorgWarner 44-66 transfer case in the 2018 F-250 Super Duty also uses MERCON LV automatic transmission fluid. This is a common practice in many Ford transfer cases. The capacity is approximately 2.0 quarts (1.9 liters). Similar to the transmission, it is critical to use only MERCON LV. Transfer case fluid changes are generally recommended at longer intervals than engine oil but should not be neglected, especially if frequently engaging 4WD or towing.

Differentials

The 2018 F-250 Super Duty can come with various differential options, primarily Dana M275 and M300 axles. The fluid specifications are crucial for proper operation and longevity.

For the Front Differential, Ford generally specifies SAE 80W-90 High Performance Gear Oil (Ford part number XY-80W90-QL) for the Dana M275. For the larger Dana M300 front differential, you might find SAE 75W-85 Synthetic Hypoid Gear Lubricant (Ford part number XO-75W85-QL). Capacities can vary from 3.0-3.2 quarts (2.8-3.0 liters) for the M275 to approximately 4.0 quarts (3.8 liters) for the M300. Always verify the specific axle and fluid type in your owner's manual.

For the Rear Differential, regardless of whether it's a Dana M275 or M300 axle, Ford typically recommends SAE 75W-140 High Performance Synthetic Rear Axle Lubricant (Ford part number XY-75W140-QL). If your F-250 is equipped with a limited-slip differential (LSD), it is absolutely essential to add a friction modifier (often included in the Ford synthetic fluid or sold separately as XL-3) to prevent chatter and ensure proper LSD operation. Capacities range from 3.5-4.0 quarts (3.3-3.8 liters) for the M275 to approximately 4.0 quarts (3.8 liters) for the M300. Differential fluid typically requires less frequent changes than engine oil, often every 30,000 to 50,000 miles, or more frequently under severe towing conditions.

Brake Fluid

Ford specifies DOT 4 Low Viscosity (LV) Motor Vehicle Brake Fluid for the 2018 F-250 Super Duty, meeting Ford specification WSS-M6C65-A2. While DOT 3 is generally compatible, DOT 4 LV is preferred for its lower viscosity in cold temperatures, which can benefit ABS and electronic stability control systems. Never use DOT 5 (silicone-based) fluid, as it is incompatible with the F-250's braking system. Brake fluid is hygroscopic, meaning it absorbs moisture over time, which reduces its boiling point and can lead to corrosion in the brake system. It is recommended to flush the brake fluid every 2-3 years or as specified in your owner's manual.

Power Steering Fluid

For the 2018 F-250 Super Duty, the power steering system typically uses MERCON ULV or MERCON LV fluid. It is crucial to check the power steering reservoir cap or your owner's manual for the exact specification. Using the incorrect fluid can lead to pump failure or steering issues. Power steering fluid does not typically have a specified change interval but should be monitored for level and condition, and flushed if contaminated or dark.

Washer Fluid

Any high-quality, commercially available windshield washer fluid is generally acceptable. Ford offers its own Premium Windshield Washer Concentrate (Ford part number ZC-32-A) or equivalent. It is advisable to use fluids with antifreeze properties in colder climates to prevent freezing in the reservoir and lines.

Diesel Exhaust Fluid (DEF)

For 6.7L Power Stroke diesel models, Diesel Exhaust Fluid (DEF) is required for the Selective Catalytic Reduction (SCR) system. The DEF must meet ISO 22241 standards and be API certified. Ford recommends Motorcraft Diesel Exhaust Fluid (Ford part number PM-27-J) or an equivalent brand that explicitly states ISO 22241 compliance and API certification. The DEF tank capacity is approximately 7.5 U.S. gallons (28.4 liters). Do not overfill. Using non-compliant DEF or contaminating the DEF can lead to costly damage to the SCR system and potentially derate engine performance. Store DEF in a cool, dry place and be aware of its shelf life, typically one year from the date of manufacture. Refill as indicated by the vehicle's DEF gauge and warnings.

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