2015 Ford Transit — Complete Fluid Type Specifications

Quick reference

Fluid	Type/Spec	Capacity
Engine oil — 3.7L V6 gasoline	SAE 5W-20 meeting Ford WSS-M2C945-A (superseded by WSS-M2C945-B1); backwards-compatible with WSS-M2C930-A	Approx. 5.7–6.0 qt (5.4–5.7 L) incl. filter — verify by engine code
Engine oil — 3.5L EcoBoost V6 gasoline	SAE 5W-30 meeting Ford WSS-M2C946-A (superseded by WSS-M2C946-B1)	Approx. 6.0 qt (5.7 L) incl. filter — verify by engine code
Engine oil — 3.2L Power Stroke I5 diesel	5W-30 or 5W-40 diesel oil meeting Ford WSS-M2C171-F1; API CJ-4/CK-4	Approx. 9–11 qt (8.5–10.4 L) incl. filter — verify in owner’s manual/OEM service info
Engine coolant	Motorcraft Orange OAT; Ford WSS-M97B44-D (orange)	~13–20 qt (12–19 L) depending on engine, wheelbase, rear heat — verify
Automatic transmission (6R80)	Mercon LV ATF; Ford WSS-M2C938-A	Service refill ~5.5–7.0 qt (5.2–6.6 L); dry fill ~12–13 qt (11–12.3 L)
Transfer case	Not applicable (2015 Transit is RWD; no transfer case)	—
Front differential	Not applicable (RWD)	—
Rear differential	API GL-5 gear oil: typically SAE 75W-85 meeting Ford WSS-M2C942-A; some heavy-duty axles/towing use SAE 75W-140 meeting Ford WSL-M2C192-A; add friction modifier for limited-slip if required	~2.5–3.5 qt (2.4–3.3 L) — fill to lower edge of fill hole; verify axle code
Brake fluid	DOT 4 Low Viscosity; Ford WSS-M6C65-A2	As needed for service/bleeding (dry fill ~1.0–1.5 L)
Power steering	Most models use EPAS (electric) — no fluid. If equipped with hydraulic PS (some cutaway/chassis): Mercon LV ATF (WSS-M2C938-A)	As needed (if hydraulic)
Windshield washer	Quality methanol-based washer fluid suitable for climate	~1.0–1.5 gal (3.8–5.7 L) depending on reservoir/options
Diesel Exhaust Fluid (DEF) — diesel only	ISO 22241-compliant AUS 32 (32.5% urea)	~4.0–6.5 gal (15–25 L) depending on tank — verify by VIN/options

Engine oil

Gasoline engines:

• 3.7L V6: Use SAE 5W-20 meeting Ford WSS-M2C945-A (superseded by WSS-M2C945-B1; older fills may list WSS-M2C930-A). Capacity is typically around 5.7–6.0 qt with filter.
• 3.5L EcoBoost: Use SAE 5W-30 meeting Ford WSS-M2C946-A (superseded by WSS-M2C946-B1). Capacity is about 6.0 qt with filter.

Diesel engine (3.2L Power Stroke): Use diesel engine oil meeting Ford WSS-M2C171-F1. In North America, high-quality API CJ-4 or CK-4 oils in 5W-30 or 5W-40 are commonly specified. Capacity is roughly 9–11 qt with filter, depending on configuration. Verify in the owner’s manual/OEM service info.

Intervals and tips:

• Follow the Intelligent Oil-Life Monitor (IOLM) for change intervals. Typical normal-service intervals are up to 7,500–10,000 miles; severe duty (idling, towing, dusty) is shorter (often ~5,000–7,500 miles).
• Always use a quality oil filter meeting OEM spec. Do not mix viscosity grades. For the EcoBoost, 5W-30 is preferred for turbo protection.

Engine coolant

The 2015 Transit uses Motorcraft Orange OAT coolant meeting Ford WSS-M97B44-D. It is orange in color.

• Capacity varies widely by engine, wheelbase, and whether the van has rear auxiliary heat: anticipate roughly 13–20 qt total.
• Typical service life is 5 years/100,000 miles initial, then every 3 years/50,000 miles thereafter.

Pitfalls:

• Do not mix Orange OAT with other Ford coolants (e.g., Yellow, Gold, or universal green). Mixing can shorten life and reduce corrosion protection. If mixed, a complete flush is recommended.
• Use a 50/50 premix with distilled water. Properly bleed air, especially on units with rear heat, to avoid heater core air pockets.

Automatic transmission fluid (6R80)

Use only Mercon LV ATF meeting Ford WSS-M2C938-A. Do not substitute Mercon V, Mercon ULV, or “universal” ATF.

• Service refill during pan/filter service is typically 5.5–7.0 qt; a dry, overhauled unit takes ~12–13 qt.
• Many OEM schedules list no routine fluid change under normal service, but a 60–100k mile service is prudent in severe use (towing, hot climates, commercial duty).

Service notes:

• Level is checked with the vehicle level and the transmission fluid at a specified temperature window; follow the service procedure and do not overfill.
• Use the correct pan/filter parts; some 6R80 variants use an integrated pan/filter assembly with a specific gasket torque pattern.

Transfer case

Not applicable on 2015 Transit (RWD only; no AWD/4x4 transfer case).

Front differential

Not applicable on 2015 Transit (RWD only).

Rear differential (final drive)

• Most Transits specify API GL-5 SAE 75W-85 gear oil meeting Ford WSS-M2C942-A. Certain heavy-duty axles/towing or high-ambient service may require SAE 75W-140 meeting Ford WSL-M2C192-A. Always confirm by axle tag/door sticker and the owner’s manual.
• Capacity generally falls between ~2.5–3.5 qt; fill to the bottom of the fill hole with the vehicle level.
• Limited-slip (Trac-Lok) axles may require friction modifier (e.g., Motorcraft XL-3) unless the chosen fluid states it already contains the additive.

Intervals and tips:

• Normal service may be “inspect only,” but severe service/towing typically calls for fluid replacement around 100k–150k miles, or immediately after water submersion.
• Clean the magnet and use new seals/crush washers as applicable.

Brake fluid

Use DOT 4 Low Viscosity brake fluid meeting Ford WSS-M6C65-A2.

• Dry system capacity is about 1.0–1.5 L; for routine service, add as needed during bleeding.
• Recommended replacement interval is every 2–3 years, or if contamination/moisture is detected. Never mix silicone DOT 5 with DOT 3/4 systems.

Power steering

Most 2015 Transit models use EPAS (electric power-assisted steering) and have no serviceable power steering fluid.

• If your cutaway/chassis configuration has hydraulic power steering, use Mercon LV ATF meeting WSS-M2C938-A. Check for leaks, hose condition, and reservoir level with the engine off.

Windshield washer fluid

Use any quality methanol-based washer fluid appropriate for your climate. Cold-weather blends help prevent freezing. Do not substitute plain water in freezing climates to avoid reservoir and line damage.

Diesel Exhaust Fluid (DEF) — diesel only

The 3.2L Power Stroke requires ISO 22241-compliant DEF (AUS 32, 32.5% urea).

• Tank capacity ranges roughly 4.0–6.5 gallons depending on wheelbase and tank option.
• Typical consumption is ~1–3% of diesel fuel used. Keep DEF above 1/4 to prevent warnings and reduced speed/no-start countdowns.

Tips:

• Store DEF sealed; shelf life shortens with heat. Never add additives or water. If contaminated, drain and refill to avoid SCR system faults.

Verify all capacities/specs by VIN in the owner’s manual or OEM service information, as they vary by engine, axle, and options (rear heat, dual rear wheels, etc.).

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