2018 Ford F-150 Fluid Capacities and Specifications

As an ASE-certified master technician, I know that using the correct fluids and lubricants is one of the most critical aspects of vehicle maintenance. Modern engines and transmissions are built to exacting standards, and the fluids that protect them are highly specialized. Using the wrong type can lead to premature wear, reduced performance, and even catastrophic failure.

This guide covers the factory-specified fluid types, specifications, and capacities for the 2018 Ford F-150. Always consult your owner's manual or OEM service information to confirm the precise requirements for your specific engine and drivetrain configuration.

Quick Reference

Fluid	Type/Spec	Capacity
Engine Oil	SAE 5W-30 (Gas, except 3.3L) / SAE 5W-20 (3.3L) / SAE 10W-30 (Diesel)	6.0 - 8.8 quarts (verify by engine)
Engine Coolant	Ford VC-13-G Motorcraft Yellow Antifreeze/Coolant	12.1 - 15.3 quarts (verify by engine)
Transmission Fluid	Ford MERCON ULV	13.1 quarts
Transfer Case Fluid	Ford MERCON LV	1.5 quarts
Front Differential Fluid	SAE 80W-90	1.9 quarts
Rear Differential Fluid	SAE 75W-85	5.5 - 7.0 pints (verify axle type)
Brake Fluid	DOT 4 LV High Performance	Fill to "MAX" line
Power Steering Fluid	Ford MERCON LV	Fill to "MAX" line
Windshield Washer Fluid	-	3.7 quarts
Diesel Exhaust Fluid (DEF)	API Certified ISO 22241	5.0 gallons

Engine Oil

The 2018 F-150 was available with multiple engines, and it's crucial to use the correct oil viscosity and specification for your specific powertrain.

• 2.7L EcoBoost V6, 3.5L EcoBoost V6, and 5.0L V8: These engines require SAE 5W-30 motor oil that meets Ford's WSS-M2C946-B1 specification. This is a synthetic blend or full synthetic oil designed to handle the high temperatures and pressures of modern turbocharged, direct-injection engines. Look for API Service SN PLUS or a newer rating on the bottle.

• 3.3L Ti-VCT V6: This engine is specified with SAE 5W-20 motor oil meeting Ford's WSS-M2C945-B1 spec.

• 3.0L Power Stroke V6 Diesel: The diesel engine has unique requirements, calling for SAE 10W-30 heavy-duty diesel oil that meets Ford’s WSS-M2C171-F1 specification and API Service CK-4.

Notes: Using a heavier or lighter weight oil than specified can interfere with the variable cam timing (VCT) system and lead to performance issues or check engine lights. Always use a quality oil filter and follow the oil life monitor for change intervals.

Engine Coolant

For 2018, Ford specified Motorcraft Yellow Antifreeze/Coolant (Ford VC-13-G). This is a Phosphate-based Organic Acid Technology (P-OAT) coolant. It is critical not to mix this with other coolant types, such as the older green IAT coolants or even Ford's previous orange OAT coolants. Mixing chemistries can cause the coolant to gel, leading to blockages, overheating, and expensive damage to the radiator and heater core.

Interval: The initial factory fill is designed to last up to 10 years or 200,000 miles. After the first service, the recommended interval is typically every 5 years or 100,000 miles. Always use a 50/50 mixture of distilled water and concentrated coolant.

Transmission Fluid

All 2018 Ford F-150s equipped with the 10-speed automatic transmission (10R80) require Ford MERCON ULV (Ultra Low Viscosity) automatic transmission fluid, which meets specification WSS-M2C949-A. This is a highly specific, full synthetic fluid with a very low viscosity. Do NOT use regular MERCON LV, MERCON V, or any "universal" ATF. Using the incorrect fluid will cause severe shifting problems and can quickly destroy the transmission.

Interval: This is considered a "fill-for-life" fluid by Ford, but many technicians recommend a fluid and filter change every 60,000 to 100,000 miles, especially for trucks used for towing or heavy hauling.

Drivetrain Fluids

Transfer Case (4WD Models): The transfer case requires Ford MERCON LV automatic transmission fluid. Note that this is different from the MERCON ULV used in the transmission.

Front Differential: The front axle requires SAE 80W-90 gear oil that meets Ford specification WSP-M2C197-A.

Rear Differential: Most 2018 F-150s use an SAE 75W-85 synthetic gear oil (Ford spec WSS-M2C945-A). Some heavy-duty or performance package models may have different requirements, such as the 9.75-inch or 10.25-inch axles, which might specify SAE 75W-140. If your truck is equipped with a limited-slip differential (LSD), you must add Friction Modifier (Ford XL-3) unless the gear oil already contains the necessary additive.

Brake and Steering Fluids

Brake Fluid: The brake system requires DOT 4 LV High Performance Motor Vehicle Brake Fluid (Ford PM-20). The "LV" (Low Viscosity) is important for the proper operation of the ABS and traction control systems. Do not use DOT 3 or DOT 5 silicone fluid.

Power Steering Fluid: The electric power-assisted steering (EPAS) system in the 2018 F-150 does not have a traditional hydraulic fluid reservoir to check or fill. Service is typically not required unless a system component is replaced.

Other Fluids

Windshield Washer Fluid: Use any quality, commercially available windshield washer solvent.

Diesel Exhaust Fluid (DEF): For models with the 3.0L Power Stroke diesel, API-certified Diesel Exhaust Fluid (ISO 22241) is required. The DEF tank is located on the passenger side of the truck, and the filler neck has a blue cap.

Using the correct, manufacturer-specified fluids is the best way to ensure your F-150 provides many years of reliable service. When in doubt, check your manual or consult a professional.

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