Maintaining the 1985 Dodge Ramcharger with the 5.9L 8-cylinder engine requires more than just a routine oil change; it demands the right lubricants to ensure longevity and reliability. This classic American vehicle was designed for rugged utility and off-road capability, and using high-quality synthetic fluids helps it handle the demands of modern driving conditions, from extreme temperature fluctuations to heavy towing loads. Proper lubrication reduces wear on critical components, extends service intervals, and keeps the engine, transmission, and drivetrain operating smoothly.
Recommended AMSOIL Products
- AMSOIL Signature Series 10W-30 100% Synthetic Motor Oil – The top choice for maximum protection, offering up to 25,000 miles of engine defense against horsepower loss and wear while handling extreme temperatures.
- AMSOIL Extended-Life 10W-30 100% Synthetic Motor Oil – An excellent balance of performance and value, providing 20,000 miles of protection with 37% more cleaning power to keep the engine running smoother.
- AMSOIL OE 10W-30 100% Synthetic Motor Oil – A budget-friendly synthetic option that fights sludge and deposits while outperforming conventional oils to meet standard maintenance needs.
- AMSOIL 10W-30 100% Synthetic High-Mileage Motor Oil – Specifically formulated for vehicles with over 75,000 miles, featuring a boosted detergent package to reduce sludge and enhance cleaning power.
- AMSOIL Oil Filter – Delivers 99% efficiency at 20 microns, providing extended service life and superior capacity for capturing small, wear-causing contaminants compared to competing filters.
- WIX Oil Filter – Features premium media that offers improvements over original equipment manufacturer (OEM)-branded filters for reliable filtration performance.
Engine Oil Specifications and Selection
The 1985 Dodge Ramcharger 5.9L 8-cylinder engine (Engine Code [W]) operates best with a viscosity grade of 10W-30 for standard conditions. The total oil capacity, including the filter replacement, is 5.9 quarts. It is crucial to check the oil level after refill and ensure the oil drain plug is torqued to 20 ft/lbs to prevent leaks. The engine oil should be changed regularly to maintain peak performance, especially if the vehicle is used for severe service such as towing, frequent short trips, or off-road driving.
For owners seeking the absolute highest level of protection, AMSOIL Signature Series 10W-30 is the preferred choice. This 100% synthetic oil is engineered to provide unsurpassed engine protection against horsepower loss and wear for up to 25,000 miles or one year. It offers 75% more protection than industry standards, making it ideal for protecting the classic V8 engine in the Ramcharger. For those who need a robust option but prefer to change fluids slightly more frequently, the AMSOIL Extended-Life 10W-30 offers up to 20,000 miles of protection. Additionally, AMSOIL OE 10W-30 is a reliable alternative that meets the requirements of the engine while fighting sludge and deposits effectively. If your Ramcharger has accumulated significant mileage over the years, the AMSOIL 10W-30 100% Synthetic High-Mileage Motor Oil is designed to reduce sludge by 67% and boost detergency to keep older engines running cleaner.
Filter Recommendations
The quality of the oil filter is just as important as the oil itself. A high-efficiency filter ensures that contaminants are removed from the circulating oil, preventing abrasive particles from damaging engine bearings and cylinder walls. For this vehicle, the AMSOIL Oil Filter is highly recommended. It is designed to allow lower restriction, keeping engine parts lubricated, and offers greater capacity for small, wear-causing contaminants than competing filters. The filter also helps reduce engine wear and offers extended service life in accordance with industry standards. Alternatively, the WIX Oil Filter is a proven option that utilizes premium media to outperform many OEM filters in filtration efficiency.
Transmission Fluid and Filters
The automatic transmission for the 1985 Ramcharger, specifically the A727 (36RH) 3-speed or the A999 (32RH) variants, requires specific synthetic fluid to ensure smooth shifting and durability. The total fill capacity for the A727 is approximately 8.3 quarts with a lockup converter and 8.6 quarts without, while the initial fill is 4 quarts. The A999 unit also requires a total fill of 8.6 quarts with an initial fill of 4 quarts.
AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid is an ideal choice for these transmissions. It withstands the rigors of heavy towing and elevated temperatures while remaining fluid in sub-zero conditions, providing reserve protection during heavy use. For a more cost-effective solution that still delivers excellent protection, the AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid protects against wear, resists sludge, and promotes smooth, shudder-free shifts. Both fluids are engineered to guard against leaks and perform well in cold weather.
To maintain transmission health, the WIX Transmission Filter is a suitable replacement. This filter features premium media that offers improvements over original equipment manufacturer-branded filters, helping to keep the transmission fluid clean and the system operating efficiently. Regular fluid changes and filter replacements are essential to prevent costly transmission problems down the road.
Cooling System and Antifreeze
The cooling system for the 5.9L engine requires the correct capacity and formulation to prevent overheating and corrosion. With the air conditioning system, the capacity is 15.3 quarts, and without it, the capacity drops to 14.3 quarts. Using the correct antifreeze is vital for protecting the engine block, radiator, hoses, and water pump from rust and freezing.
AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a unique poly-organic acid (OAT) formulation that allows for use in a wide variety of vehicles. It is an ethylene glycol 50/50 pre-mix that provides protection up to 150,000 miles or 5 years. This AMSOIL Propylene Glycol Antifreeze and Engine Coolant is phosphate-, nitrate-, nitrite-, silicate-, borate-, and amine-free, making it compatible with all other antifreeze colors and safe for all cooling system metals and gaskets. For those who prefer a concentrate to mix with distilled water, the Propylene Glycol Antifreeze and Engine Coolant offers a robust alternative. It is concentrated and requires mixing, providing protection up to 150,000 miles or 5 years in passenger cars and light trucks, with extended service life in heavy-duty applications. It greatly surpasses standards for metallic corrosion and erosion.
Gear Lubes for Differentials and Transfer Case
The 1985 Dodge Ramcharger features various gear sets that require high-performance lubrication. The transfer case, such as the NP208, holds 5.9 pints. For the differentials, capacities vary by unit: the front Spicer 44 takes 5.7 pints, the front Spicer 60F takes 6.6 pints, the rear Spicer 60 (limited slip) takes 5.9 pints, the rear Spicer 70 takes 7 pints, and the rear with an 8.25 RG takes 4.4 pints. Note that for limited slip differentials, an additive like 6.5% Mopar Trac-loc may be required if using specific formulations.
AMSOIL SEVERE GEAR® 100% Synthetic Gear Lubes are designed to handle these demands. The 75W-140, 80W-90, and 75W-110 grades are recommended depending on the specific application and temperature requirements. These gear lubes offer advanced protection against wear, control thermal runaway, and protect against rust and corrosion. They also help reduce operating temperatures and extend the life of seals, gears, and equipment. The AMSOIL SEVERE GEAR 75W-90 is ideal for front and rear differentials requiring higher viscosity, while the 80W-90 and 75W-90 grades are excellent choices for rear differentials and manual transmissions, including the 4-speed A435 unit which holds 7 pints.
Other Fluids: Brakes, Power Steering, and Small Engine Oil
Maintaining the hydraulic systems and auxiliary fluids is crucial for safety and convenience. The Ramcharger requires DOT 3 hydraulic AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid, meeting MS-4574 specifications. This fluid provides excellent ABS and traction-control responsiveness with a stable viscosity over a wide temperature range, ensuring reliable braking performance in all conditions.
For the power steering system, which uses fluid type PS009, the AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid is the recommended choice. It reduces friction, helps seals remain soft to prevent leaks, and resists heat for long fluid life. It also offers strong anti-wear protection and excellent high- and low-temperature performance for quiet operation.
For other small engine applications or specific lubrication needs within the vehicle’s auxiliary systems, the AMSOIL 10W-30 100% Synthetic Small-Engine Oil is a versatile option. It protects engines up to 200 hours, helps extend engine life, and is rust-inhibited to maximize power and reduce maintenance costs.
About the Vehicle
The 1985 Dodge Ramcharger represents a unique era in American automotive history, blending the rugged utility of a truck with the comfort of a station wagon. Based on the Dodge Dakota and Ram pickup chassis, the Ramcharger featured a fixed roof and rear seating, making it a popular choice for families who needed to haul cargo or equipment without sacrificing passenger space. The 5.9L (360 cubic inch) V8 engine, identified by the [W] code in 1985, was a powerhouse known for its robust torque output, perfectly suited for the vehicle’s intended off-road and towing capabilities.
During the 1980s, the Ramcharger was a staple for owners in rural areas and those engaged in recreational activities like hunting or off-roading. Its body-on-frame construction provided durability and stability on rough terrain, while the independent front suspension offered a smoother ride on paved roads compared to many other trucks of the time. The vehicle’s design allowed for a wide range of aftermarket modifications, and it remains a beloved classic among enthusiasts today. With a reputation for being tough and reliable, the Ramcharger required a steady supply of high-quality maintenance products to keep its mechanical systems running as intended. Owners of this vehicle understand that proper lubrication is the key to preserving its classic character and ensuring it can continue to tackle the trails or haul heavy loads for years to come.