Keeping your 1986 Mitsubishi Pickup running reliably starts with selecting the right lubricants for its 2.0L G63B engine. This classic truck was built for utility and durability, but like any vehicle with over three decades of history, it demands proper maintenance to prevent wear and extend its operational life. Using the correct viscosity and type of fluid ensures that components remain protected against friction, heat, and corrosion, regardless of whether you are driving on rough terrain or cruising on paved roads.
Recommended AMSOIL Products
- AMSOIL Signature Series 10W-30 100% Synthetic Motor Oil – Provides maximum protection against horsepower loss and wear, offering 75% more engine protection than industry standards for this engine.
- AMSOIL Extended-Life 10W-30 100% Synthetic Motor Oil – Delivers 37% more cleaning power to help keep the engine running smoother for longer service intervals.
- AMSOIL OE 10W-30 100% Synthetic Motor Oil – A cost-effective option that fights sludge and deposits with a 100% synthetic formulation designed to meet original equipment requirements.
- AMSOIL 10W-30 100% Synthetic High-Mileage Motor Oil – Specifically formulated for vehicles with over 75,000 miles, featuring boosted detergents and reduced sludge to help older engines perform better.
- WIX Oil Filter – Features premium media that offers improvements over original equipment manufacturer branded filters to ensure clean oil circulation.
For the 1986 Mitsubishi Pickup equipped with the 2.0L G63B engine, AMSOIL offers four distinct synthetic motor oil choices. The Signature Series is the top-tier option, boasting superior thermal stability and protection that allows for extended drain intervals of up to 25,000 miles or one year under normal service conditions. This oil contains a unique blend of additives that fight sludge formation and protect turbochargers, ensuring maximum power retention over time. If your vehicle operates in more extreme climates or you prefer a slightly more frequent change schedule, the Extended-Life 10W-30 offers a balance of high-performance cleaning power and protection, guaranteeing up to 20,000 miles of engine care. It is particularly effective at neutralizing acidic byproducts and keeping internal components free of carbon buildup.
Owners who are budget-conscious but still demand synthetic quality will find the OE 10W-30 an excellent choice. This fluid provides a high-performance synthetic base that fights sludge and deposits while meeting original equipment specifications. For those driving higher mileage trucks, the High-Mileage 10W-30 is the specialized solution. It features a unique chemistry designed for vehicles exceeding 75,000 miles, containing enhanced anti-wear additives and a boosted detergent package that reduces sludge by 67%. This helps restore engine performance and reduces oil consumption in older engines. Regardless of the oil chosen, a change interval includes draining 3.9 quarts of oil with a filter replacement. The torque specification for the oil drain plug should be set between 26 and 32 ft-lbs to ensure a proper seal without risking damage to the drain plug threads.
Maintaining the cooling system is equally vital for the longevity of the G63B engine. The cooling system capacity for this vehicle is 9.5 quarts. AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is an ideal choice, featuring a unique poly-organic acid formulation that protects against corrosion and is compatible with all cooling system metals, gaskets, and hoses. It is a 50/50 pre-mix ethylene glycol solution that provides protection for up to 150,000 miles or five years. For those who prefer to mix their own coolant, the AMSOIL Propylene Glycol Antifreeze and Engine Coolant is a concentrated option. It requires mixing with distilled water and offers protection up to 150,000 miles in passenger cars and light trucks. This formulation is phosphate-, nitrate-, nitrite-, silicate-, borate-, and amine-free, ensuring long-term corrosion resistance and excellent heat transfer capabilities.
Transmission and Gear Lubrication
The health of your Mitsubishi Pickup’s drivetrain relies heavily on using the correct transmission and gear fluids. For automatic transmissions, such as the A904 3-speed found in many of these models, AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid is the premium recommendation. It withstands the rigors of heavy towing and elevated temperatures while remaining fluid in sub-zero conditions. The full total fill capacity for this transmission is 7.2 quarts, with an initial fill capacity of 4 quarts. Alternatively, the AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid offers excellent performance with a focus on smooth, shudder-free shifts and resistance to harmful sludge formation.
For manual transmissions and transaxles, AMSOIL 75W-90 Manual Transmission & Transaxle Gear Lube is recommended. It is friction-modified to protect brass synchronizers and provides outstanding cold-flow properties. The fill capacity for the 4WD KM132-8 transmission is 4.6 pints, while the RWD version holds 4.9 pints. This gear lube offers long service life and inhibits rust and corrosion effectively. Transfer cases require the same 75W-90 AMSOIL 75W-90 Manual Transmission & Transaxle Gear Lube, with a capacity of 4.6 pints for the U/K TRC unit. Proper torque specifications for fill and drain plugs should be observed to prevent leaks, with a recommended torque of 22-25 ft/lbs for transfer case components.
Differential lubrication varies depending on the specific axle and ambient temperature. For front differentials requiring GL-5 lubricants in temperatures between -34°F and -23°F, AMSOIL SEVERE GEAR 80W-90 100% Synthetic Gear Lube is ideal, with a capacity of 2.3 pints. In warmer conditions above -23°F, the 80W-90, 85W-90, or 90-weight equivalents are suitable. For limited slip differentials, which require a specific friction modifier, AMSOIL SEVERE GEAR 75W-90 or AMSOIL SEVERE GEAR 75W-110 are excellent choices to prevent chatter and ensure smooth operation. The rear limited slip differential capacity is 3.2 pints. These AMSOIL SEVERE GEAR 75W-90 lubricants contain friction modifiers that provide advanced protection against wear and thermal runaway, essential for heavy-duty use and preventing the “chatter” common in limited slip units.
Brake Fluid and Power Steering
Safety systems require fluid maintenance to function correctly. The hydraulic brake fluid for this vehicle is a DOT 3 specification. AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid offers excellent responsiveness for ABS and traction-control systems. It maintains a stable viscosity over a wide temperature range, preventing the spongy pedal feel that can occur with degraded fluid. For the power steering system, which uses a fluid equivalent to DEXRON-II, the AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid can be utilized. This ensures compatibility with the system seals and provides the necessary hydraulic properties for smooth steering assist.
For seasonal storage, it is advisable to treat the fuel system to prevent degradation. AMSOIL Gasoline Stabilizer helps keep fuel fresh for up to 12 months, fighting ethanol corrosion and varnish buildup. Additionally, AMSOIL P.i. Performance Improver Gasoline Additive can restore up to 14% of lost horsepower and clean fuel injectors, ensuring the engine runs efficiently even after long periods of inactivity. These additives are compatible with capless fuel systems and help prevent pre-ignition knock, making them valuable for maintaining the performance of the G63B engine.
About the Vehicle
The 1986 Mitsubishi Pickup is a quintessential example of the rugged, utility-focused trucks that dominated the light-duty market during the mid-1980s. Built on a durable platform, this vehicle was designed primarily for work and everyday driving rather than high-speed luxury. The 2.0L 4-cylinder engine, identified by the G63B code, was a workhorse known for its simplicity and ease of maintenance. While it did not offer the high horsepower figures of modern engines, it provided sufficient power for hauling cargo and towing light trailers, making it a favorite among owners who prioritized reliability over raw speed.
This generation of the Mitsubishi Pickup featured a boxy, functional design with a focus on practicality. The suspension and chassis were engineered to handle rough terrain and heavy loads, which contributed to the vehicle’s longevity. Many owners of this era’s trucks appreciate the mechanical simplicity that allows for DIY repairs and maintenance, a trait that has kept these vehicles on the road for decades. The 2.0L engine was widely used across various Mitsubishi models, meaning parts availability remains relatively accessible for enthusiasts. Its reputation is built on toughness and durability, capable of enduring harsh conditions with minimal fuss when properly maintained. Today, these trucks are often sought after by collectors and enthusiasts looking for a reliable, no-nonsense vehicle or a project truck that can be restored to its original glory.