The 2018 Ford Transit-250 with the 3.7L 6-cylinder engine (Engine Code M 99M 3 Flex) is a workhorse built for demanding tasks. Maintaining this vehicle requires precise fluid specifications to ensure longevity and performance. Using the correct viscosity and type of lubricant is critical for the engine’s internal components, the transmission’s smooth operation, and the overall reliability of the vehicle under heavy loads or extreme temperatures. AMSOIL offers a comprehensive range of 100% synthetic lubricants designed to exceed factory standards and provide superior protection for this specific truck.
Recommended AMSOIL Products
When equipping your 2018 Ford Transit-250 for a fluid change, selecting the right products is essential for maximizing engine life and component protection. The following AMSOIL items are specifically recommended for the 3.7L 6-cylinder engine and its associated systems.
- AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil – Provides up to 25,000 miles of protection and superior defense against horsepower loss and wear.
- AMSOIL Extended-Life 5W-20 100% Synthetic Motor Oil – Offers 20,000 miles of protection with enhanced cleaning power to keep the engine running smoother.
- AMSOIL OE 5W-20 100% Synthetic Motor Oil – A cost-effective synthetic option that fights sludge and deposits while protecting the engine.
- AMSOIL 5W-20 100% Synthetic High-Mileage Motor Oil – Formulated specifically for vehicles over 75,000 miles with boosted detergents and reduced sludge.
- AMSOIL Oil Filter – Designed for maximum filtering efficiency and extended service life to keep engine parts lubricated.
- WIX XP Oil Filter – Premium media offers improvements over original equipment manufacturer (OEM)-branded filters.
- WIX Oil Filter – Premium media offers improvements over original equipment manufacturer (OEM)-branded filters.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A pre-mixed ethylene glycol solution that protects cooling system metals and hoses.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated option that requires mixing and offers protection up to 150,000 miles or 5 years.
- AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Withstands heavy towing and elevated temperatures while remaining fluid in sub-zero conditions.
- AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Provides reliable protection against wear for the transmission system.
- AMSOIL SEVERE GEAR® 75W-85 100% Synthetic Gear Lube – Advanced protection for rear standard and limited-slip differentials, controlling thermal runaway and rust.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Ensures excellent ABS responsiveness and stable viscosity over a wide temperature range.
Proper lubrication extends the service intervals between maintenance while ensuring the vehicle operates at peak efficiency. The 3.7L 6-cylinder engine in the Transit-250 benefits significantly from high-quality synthetic oils that resist breakdown under the high thermal loads generated during towing or hauling. Below, we detail the specific requirements for the engine, transmission, and other vital systems.
Engine Oil Specifications and Protection
The heart of the 2018 Ford Transit-250 is the 3.7L 6-cylinder engine. For this engine, AMSOIL recommends a 5W-20 viscosity for all temperatures to ensure optimal cold starts in extreme climates. The oil capacity for a standard change, including the filter, is 6 quarts. It is crucial to check the oil level after refilling and to torque the drain plug to 20 ft/lbs. If you utilize E85 or M85 fuels, AMSOIL advises using the appropriate viscosity and extending the drain interval only through oil analysis.
For the maximum protection possible, AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil is the top choice, offering up to 25,000 miles of protection in normal service. It provides 75% more engine protection against horsepower loss compared to conventional standards. For those seeking extended performance with slightly shorter intervals, AMSOIL Extended-Life 5W-20 100% Synthetic Motor Oil guarantees 20,000 miles of protection and helps keep the engine running smoother with 37% more cleaning power. Additionally, AMSOIL OE 5W-20 100% Synthetic Motor Oil is an excellent option for those who want to outperform conventional oils without breaking the budget. For vehicles that have accumulated over 75,000 miles, the AMSOIL 5W-20 100% Synthetic High-Mileage Motor Oil features a unique chemistry with boosted detergents to reduce sludge and restore engine performance.
Matching the oil with a high-quality filter is just as important as the oil itself. The AMSOIL Oil Filter offers 99% filtration efficiency at 20 microns and lower restriction, which helps reduce engine wear. Alternative options include the WIX XP Oil Filter for premium performance or the standard WIX Oil Filter.
Transmission, Differential, and Cooling System
The automatic transmission in the 2018 Ford Transit-250, specifically the 6-speed 6R80, requires precise fluid to handle the rigors of its operation. A total fill requires 13.1 quarts, while an initial fill is approximately 3.5 quarts. AMSOIL recommends the AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid for superior protection against heavy towing, elevated temperatures, and challenging terrain. For a value-oriented solution, the AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid provides effective wear protection.
The rear differential requires 100% synthetic AMSOIL SEVERE GEAR® 75W-85 100% Synthetic Gear Lube. For a standard rear differential, the capacity is 5.9 pints, while a limited-slip rear differential requires 5.7 pints of AMSOIL SEVERE GEAR® 75W-85 100% Synthetic Gear Lube. This synthetic lube is designed to control thermal runaway and protect against rust and corrosion, extending the life of the gears and seals.
For the cooling system, the 2018 Ford Transit-250 holds 16.4 quarts with the AHR16.4 radiator or 14.9 quarts with the standard O radiator. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a pre-mixed 50/50 ethylene glycol solution that exceeds OEM requirements and protects all cooling system metals. Alternatively, the AMSOIL Propylene Glycol Antifreeze and Engine Coolant is a concentrated formula that can be mixed with distilled water for those who prefer a custom mix, offering protection up to 150,000 miles or 5 years.
Brake Fluid and Maintenance Additives
Maintaining the braking system is vital for safety. The recommended brake fluid for the 2018 Ford Transit-250 meets Ford specification WSS-M6C65-A2. The AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid ensures excellent responsiveness for ABS and traction-control systems while maintaining a stable viscosity across extreme temperatures.
For additional vehicle care, the AMSOIL P.i.® Performance Improver Gasoline Additive can help restore horsepower and clean GDI fuel injectors. For seasonal storage, the AMSOIL Gasoline Stabilizer keeps fuel fresh for up to 12 months, protecting against varnish and gum buildup.
About the Vehicle
The 2018 Ford Transit-250 represents a significant shift in the commercial van market, offering a blend of traditional body-on-frame durability and unibody ride quality. Built at the Ohio Assembly Plant in Columbus, Ohio, the Transit is Ford’s direct response to competitors like the Mercedes-Benz Sprinter and the Ram ProMaster. The 250 model sits comfortably between the light-duty Transit-150 and the heavy-duty Transit-350, offering a balance of payload capacity and maneuverability that makes it a favorite among small business owners, contractors, and fleet operators.
Equipped with the 3.7L 6-cylinder engine (often referred to as the Duratec-37), this van delivers reliable power with a focus on fuel efficiency for a naturally aspirated engine of its era. While the 3.7L V6 may not match the peak horsepower of the later V6 turbocharged or diesel options, it is renowned for its simplicity, durability, and lower maintenance costs. It produces a solid output that handles everyday hauling and delivery routes with ease, making it a versatile choice for a wide range of applications.
Owners of the Transit-250 generally appreciate the spacious interior, which allows for easy conversion into various configurations, from cargo vans to passenger shuttles. The design prioritizes practicality, with high-mounted cargo doors and a flat floor that maximizes utility. The vehicle’s reputation is built on its capability to serve as a mobile office or a dedicated delivery platform that can withstand years of daily use.
However, like any work vehicle, the Transit-250 can face specific challenges that proper lubrication can help mitigate. One common issue for high-mileage vans is oil consumption and sludge buildup, particularly if the vehicle is used for stop-and-go delivery work where the engine spends a lot of time at lower RPMs. Using a high-quality synthetic motor oil with a robust detergent package can help mitigate sludge and reduce oil consumption over time. Another common problem is the buildup of carbon in the fuel system, which can lead to reduced fuel economy and rough idling. Regular use of a high-quality fuel system cleaner like AMSOIL P.i. can restore injector flow and improve combustion efficiency.
Drivers who use the Transit for heavy towing may also experience higher transmission temperatures, which can degrade conventional fluids faster than expected. Synthetic transmission fluids are engineered to withstand these elevated temperatures better, preventing the breakdown that leads to shifting issues or premature wear. Additionally, in regions where the van is used in harsh winter conditions, the brake fluid can absorb moisture over time, leading to a lower boiling point and potential issues with pedal feel or ABS activation. Switching to a high-performance synthetic brake fluid helps prevent this moisture absorption and maintains consistent braking performance regardless of the weather.
By addressing these specific needs with the right fluids, owners can extend the life of their 2018 Ford Transit-250, ensuring it remains a reliable asset for years to come. The combination of a durable engine platform and superior synthetic lubricants creates a winning formula for long-term ownership satisfaction.