The 2018 Ram 3500 Pickup equipped with the 5.7L Hemi engine requires specific fluid formulations to handle its demanding work capabilities. Whether you are towing heavy loads, navigating extreme temperatures, or simply commuting to work, using the correct lubricants is essential for maintaining engine longevity and transmission reliability. This vehicle operates under significant stress, particularly when hauling, which can push standard conventional fluids beyond their limits.
Recommended AMSOIL Products
For the 2018 Ram 3500 5.7L engine, the primary lubrication requirement is a 5W-20 viscosity grade. Below are the top-tier AMSOIL options recommended for this application, each tailored to different maintenance schedules and vehicle mileages.
- AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil – The ultimate protection for extreme temperatures and heavy towing, offering up to 25,000 miles of service intervals.
- AMSOIL Extended-Life 5W-20 100% Synthetic Motor Oil – Provides enhanced cleaning power and up to 20,000 miles of protection for drivers who want extended intervals without sacrificing performance.
- AMSOIL OE 5W-20 100% Synthetic Motor Oil – An excellent choice for OEM replacement, effectively fighting sludge and deposits while providing reliable protection for up to 15,000 miles.
- AMSOIL 5W-20 100% Synthetic High-Mileage Motor Oil – Formulated specifically for vehicles with over 75,000 miles to reduce oil consumption, minimize sludge, and revitalize engine seals.
- WIX Oil Filter – A high-performance filter designed to trap contaminants more effectively than standard OEM filters, ensuring clean oil circulates through your 5.7L Hemi.
Transmission and Drivetrain Protection
The 2018 Ram 3500 features the 66RFE automatic transmission, a robust unit designed for heavy-duty applications but still susceptible to the high heat generated during towing and hauling. Maintaining this transmission is critical for smooth shifting and long-term durability. The factory fluid often breaks down under the extreme stress of commercial use or severe driving conditions. AMSOIL offers synthetic solutions that remain fluid in sub-zero temperatures while resisting thermal breakdown in extreme heat.
For the automatic transmission, we recommend using AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid. This fluid is engineered to withstand the rigors of heavy towing, elevated temperatures, and challenging terrain. It provides reserve protection during heavy use and abuse, helping to extend the life of the transmission clutch packs and seals. Alternatively, the AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid offers a more budget-friendly option that still protects against wear, resists sludge, and promotes smooth, shudder-free shifts.
The total fill capacity for the 6-speed 66RFE transmission in 4WD models is approximately 16.9 quarts. For those seeking even greater protection for the drivetrain components, including the front and rear differentials, AMSOIL SEVERE GEAR 75W-85 100% Synthetic Gear Lube is the superior choice. This lubricant contains specialized friction modifiers for limited-slip applications and helps control thermal runaway, reducing operating temperatures and extending the life of seals and equipment. It protects against rust and corrosion, making it ideal for the varying environments where a Ram 3500 is often operated.
Coolant and Brake Fluid Specifications
Keeping the cooling system functional is paramount for the 5.7L Hemi, which is an air-cooled oil system but still relies heavily on liquid coolant to manage cylinder head temperatures under load. The factory coolant capacity is approximately 18.3 quarts. To ensure long-lasting corrosion protection and freeze point reliability, the AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is an ideal choice. This unique poly-organic acid (OAT) formulation exceeds OEM requirements and offers protection for up to 150,000 miles or five years. It is compatible with all cooling system metals, gaskets, and hoses, and is free of phosphates, nitrates, and borates.
For the braking system, maintaining a high boiling point is crucial to prevent brake fade during heavy-duty use. The 2018 Ram 3500 requires a DOT 3 fluid meeting MS-4574 specifications. The AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid provides excellent ABS and traction-control responsiveness. Its stable viscosity over a wide temperature range ensures consistent pedal feel and prevents the formation of water vapor, which can lead to brake failure.
Finally, do not overlook fuel system health. The 5.7L engine, especially with modern Direct Injection technology, benefits greatly from regular fuel additive use to prevent carbon buildup. AMSOIL P.i. Performance Improver restores up to 14% horsepower, cleans GDI fuel injectors to 100% flow rate, and reduces pre-ignition knock. It helps prevent carbon rap and maintains optimal fuel economy.
Additionally, for air filtration, WIX Air Filters offer premium media that improves over original equipment manufacturer-branded filters, ensuring the engine breathes efficiently. For seasonal storage, consider AMSOIL Gasoline Stabilizer to keep fuel fresh for up to 12 months and protect against varnish buildup.
About the Vehicle: 2018 Ram 3500 Pickup
The 2018 Ram 3500 Pickup represents the pinnacle of heavy-duty pickup truck capability in its class. Part of Ram’s fourth-generation HD lineup, the 3500 was designed to bridge the gap between consumer utility and commercial-grade strength. When paired with the 5.7L Hemi V8 engine, this truck offers a compelling blend of familiar V8 power and serious towing capacity. The Hemi, known for its smooth power delivery and robust torque curve, provides ample power for moving large loads, whether that involves fifth-wheel trailers, large boats, or heavy construction equipment.
Owners of the 2018 Ram 3500 often appreciate the truck’s ride quality, which was significantly refined compared to previous generations. The suspension tuning strikes a balance between carrying payload and maintaining a comfortable ride when not under load. The interior of the 2018 model year also saw a notable upgrade in technology and materials, with improved infotainment systems and more driver-centric ergonomics. However, the vehicle’s primary reputation is built on its brute strength. With a Gross Combined Weight Rating (GCWR) that can exceed 35,000 pounds in certain configurations, the 3500 is capable of pulling massive weights that rival full-size diesel trucks in the eyes of many consumers. The 5.7L engine is favored by those who want the towing capability without the complex emissions systems and higher maintenance costs associated with the Cummins diesel option.
Despite its rugged nature, the 2018 Ram 3500 is not immune to the issues common with high-stress heavy-duty vehicles. One of the most common problems owners encounter is premature wear on the transmission during heavy towing. The stock torque converter and clutch packs can heat up rapidly, leading to fluid breakdown and shudder issues. Using a high-performance synthetic transmission fluid like AMSOIL Signature Series Multi-Vehicle can mitigate this by maintaining viscosity at high temperatures and providing a thermal buffer.
Another frequent concern with the 5.7L Hemi in Ram trucks is oil consumption and carbon buildup, particularly on the intake valves if the vehicle is driven primarily on short trips or under heavy load. Over time, this can lead to reduced efficiency and rough idling. The use of AMSOIL P.i. Performance Improver is a proven method to clean injectors and intake valves, helping to restore lost horsepower and smooth out engine operation. Additionally, the oil system can suffer from sludge accumulation if long intervals are ignored or if low-quality oil is used. AMSOIL’s synthetic motor oils are specifically formulated to resist oxidation and sludge, keeping the engine internals clean.
Cooling system failures are also a potential issue, as the 5.7L Hemi can run quite hot when pulling heavy loads. Radiator caps failing or coolant boiling over can lead to overheating, which is detrimental to the engine’s lifespan. A high-quality antifreeze like AMSOIL Antifreeze & Coolant ensures that the cooling system operates efficiently even when the truck is working at its peak capacity, protecting the aluminum components from corrosion and freezing damage. Finally, the front and rear differentials, which handle the immense torque of the V8, can suffer from gear wear and limited-slip clutch chatter. Switching to a synthetic SEVERE GEAR 75W-85 Gear Lube with advanced friction modifiers can eliminate noise and protect the gears from thermal breakdown, ensuring the drivetrain lasts for years of hard work.
By understanding the specific needs of the 2018 Ram 3500 5.7L, owners can take proactive steps to maintain their vehicle. The combination of proper oil changes, quality filters, and specialized fluids for the transmission, coolant, and drivetrain transforms routine maintenance into a strategy for long-term reliability. Whether the truck is used for hauling livestock on a farm or toting a large RV on the highway, the right lubricants make all the difference in ensuring the vehicle remains a dependable workhorse.