2018 Ford F-350 Super Duty Fluid Type Specs

Quick reference

*Capacity varies by configuration and engine. Always verify with your owner's manual or OEM service information.

Engine Oil

The 2018 Ford F-350 Super Duty was offered with two primary engine options: the 6.2L V8 gasoline engine and the 6.7L Power Stroke V8 turbo diesel engine. Each requires a specific type and viscosity of engine oil.

For the 6.2L V8 gasoline engine, Ford specifies SAE 5W-30 engine oil meeting Ford WSS-M2C946-B1. This specification generally aligns with API SN Plus or newer ratings, which are designed to protect against low-speed pre-ignition (LSPI) in turbocharged gasoline direct-injection engines, even though the 6.2L is naturally aspirated. It's crucial to use an oil that explicitly meets this Ford specification to ensure proper engine lubrication and warranty compliance. The typical oil capacity for the 6.2L is approximately 7.0 quarts with a filter change.

For the 6.7L Power Stroke V8 turbo diesel engine, Ford requires SAE 10W-30 engine oil that meets Ford WSS-M2C171-F1. This specification is aligned with API CK-4, which is formulated for high-speed four-stroke diesel engines designed to meet 2017 model year on-highway and Tier 4 non-road exhaust emission standards. It provides enhanced protection against oxidation, shear stability, and aeration compared to older specifications. The 6.7L Power Stroke has a substantial oil capacity of around 13.0 quarts with a filter change.

Intervals and Pitfalls: Ford recommends oil change intervals typically ranging from 7,500 to 10,000 miles or every 6-12 months, whichever comes first, for normal operating conditions. However, severe duty cycles (e.g., heavy towing, excessive idling, dusty conditions) may necessitate more frequent changes. Always refer to your owner's manual for the precise maintenance schedule for your specific vehicle and driving conditions. Using an incorrect oil viscosity or a non-compliant specification can lead to increased engine wear, reduced fuel economy, and potential warranty voidance.

Engine Coolant

The 2018 Ford F-350 Super Duty utilizes Motorcraft Orange Antifreeze/Coolant, which is an Organic Acid Technology (OAT) coolant. The Ford specification for this coolant is WSS-M97B44-D. This coolant is typically orange in color and is designed for extended life, offering protection against corrosion and freezing for up to 10 years or 200,000 miles, whichever comes first.

Intervals and Pitfalls: While advertised as "lifetime fill" under normal conditions, it's generally good practice to consider a coolant flush and refill around the 10-year mark, especially if heavy-duty use is common. Never mix different types or colors of coolant. Mixing OAT with other technologies like HOAT (Hybrid Organic Acid Technology) or IAT (Inorganic Acid Technology) can lead to chemical incompatibilities, gel formation, reduced corrosion protection, and potential damage to the cooling system components. Always use Motorcraft Orange or an aftermarket equivalent that explicitly states compliance with Ford WSS-M97B44-D. Coolant capacity varies significantly based on engine and cabin heater configurations, ranging from approximately 16 to 29 quarts.

Transmission Fluid

The 2018 Ford F-350 Super Duty, whether equipped with the TorqShift G 6-speed automatic (6.2L gasoline) or the TorqShift 6R140 6-speed automatic (6.7L diesel), requires MERCON LV automatic transmission fluid. The Ford part number for this fluid is typically XT-10-QLVC. MERCON LV is a low-viscosity, fully synthetic fluid designed for improved fuel economy and enhanced durability.

Intervals and Pitfalls: Ford generally recommends transmission fluid changes for severe duty applications at intervals around 30,000 to 60,000 miles. For normal use, some may consider it a "fill for life" fluid, but many technicians recommend a fluid and filter change between 60,000 and 100,000 miles to maximize transmission longevity. Never use a universal ATF or any fluid that does not explicitly state MERCON LV compatibility. Using the incorrect fluid can lead to harsh shifts, transmission slippage, overheating, and catastrophic internal damage. The initial fill/dry capacity is approximately 17.5 quarts, but a drain and refill will use less.

Transfer Case Fluid

For 4WD and AWD models of the 2018 Ford F-350 Super Duty, the transfer case (likely a BorgWarner 44-70 or similar) also specifies MERCON LV automatic transmission fluid. This ensures proper lubrication and operation of the transfer case