Keeping your 1987 Subaru BRAT running smoothly requires more than just a quick oil change; it demands a comprehensive approach to lubrication that respects the vehicle’s aging components and unique engineering. The EA81 engine, designed for reliability in both urban and rugged terrain, still benefits greatly from the advanced protection offered by high-quality synthetic lubricants. Whether you are maintaining a daily driver or preserving a classic vehicle for weekend enjoyment, selecting the right fluids can significantly extend the life of your engine and transmission while ensuring consistent performance in varying weather conditions. Proper lubrication not only reduces wear but also helps manage the heat and friction inherent in older mechanical systems, making the difference between a rough-running vintage car and a well-oiled machine.
Recommended AMSOIL Products
- AMSOIL Signature Series 10W-30 100% Synthetic Motor Oil – Provides unsurpassed protection against horsepower loss and wear for up to 25,000 miles, with 75% more engine protection than conventional oils. (4.4 quarts capacity with filter).
- AMSOIL Extended-Life 10W-30 100% Synthetic Motor Oil – Features 37% more cleaning power to help keep the engine running smoother for up to 20,000 miles.
- AMSOIL OE 10W-30 100% Synthetic Motor Oil – A trusted formulation that fights sludge and deposits while outperforming conventional oils for standard service intervals.
- AMSOIL 10W-30 100% Synthetic High-Mileage Motor Oil – Specifically engineered for vehicles with over 75,000 miles, featuring enhanced anti-wear additives and boosted detergent packages to reduce sludge and extend engine life.
- AMSOIL Oil Filter – Delivers 99 percent filtering efficiency at 20 microns, allowing lower restriction to keep engine parts lubricated and capturing small contaminants that cause wear.
- WIX Oil Filter – A premium aftermarket option that offers improvements over original equipment manufacturer-branded filters for reliable filtration.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – An ethylene glycol 50/50 pre-mix formulation that provides protection for up to 150,000 miles or 5 years, safeguarding all cooling system metals, gaskets, and hoses.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated option requiring mixing with water, offering protection up to 150,000 miles or 5 years for passenger cars and light trucks.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Designed to withstand heavy towing, elevated temperatures, and challenging terrain while remaining fluid in sub-zero conditions.
- AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Resists harmful sludge, guards against leaks, and promotes smooth, shudder-free shifts with excellent cold-weather performance.
- AMSOIL SEVERE GEAR® 80W-90 100% Synthetic Gear Lube – Contains friction modifiers for limited-slip applications and helps reduce operating temperatures to extend seal and equipment life.
- AMSOIL SEVERE GEAR® 75W-90 100% Synthetic Gear Lube – Provides advanced protection against wear and rust while controlling thermal runaway in front and rear differentials.
- AMSOIL SEVERE GEAR® 75W-110 100% Synthetic Gear Lube – An alternative viscosity for demanding conditions, offering long oil and seal life with excellent thermal control.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent ABS and traction-control responsiveness with stable viscosity across a wide temperature range for safer stopping power.
The engine compartment of your 1987 Subaru BRAT contains a 1.8L EA81 engine that requires precise attention to lubrication to maintain its integrity. The recommended oil grade for this vehicle includes 10W-30, suitable for temperatures below 32°C, though 10W-40 or 10W-50 can be used in colder conditions, and 30 or 20W-40 for hotter climates. It is crucial to note that the total capacity is 4.4 quarts when the filter is replaced, and you should check the oil level after refilling. The drain plug torque specification is between 29 and 33 ft/lbs. Choosing the correct oil grade and viscosity ensures that the engine receives adequate protection across a range of driving temperatures, reducing the likelihood of oil thickening in the cold or thinning excessively in the heat.
In addition to motor oil, the transmission system requires specific attention depending on whether your BRAT has a manual or automatic setup. For automatic transmissions, the total fill capacity is 10 quarts, with an initial fill of 2.6 quarts. The system utilizes TX86 transmission fluid specifications. Synthetic options like the AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid provide superior protection against the rigors of heavy towing and elevated temperatures. For manual transmissions, such as the TM45F and TW70F models found in 4WD and FWD variants, capacities range between 5.3 and 5.9 pints. These systems require GL-5 compatible gear lubes, typically in 80W-90 or 75W-90 viscosities, to handle the mechanical stresses of shifting gears and driving in diverse conditions.
Cooling system maintenance is equally critical for preserving the longevity of the EA81 engine. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant capacity for the radiator is 6.3 quarts. This coolant is a pre-mixed 50/50 formulation that is compatible with all other antifreeze colors and does not contain phosphates, nitrates, or borates. This protects all cooling system metals, gaskets, and hoses while offering protection for up to 150,000 miles. For those who prefer a concentrated solution, the AMSOIL Propylene Glycol Antifreeze and Engine Coolant can be mixed with distilled or high-quality water to achieve the same level of corrosion and erosion protection.
Vehicle Background
The 1987 Subaru BRAT, short for “Bi-Drive Recreational All-terrain Transporter,” holds a unique place in automotive history as one of the few vehicles to be classified as a passenger car despite having truck-like features. Based on the Subaru Leone platform, this iteration of the BRAT is powered by the 1.8L EA81 engine, a horizontally opposed four-cylinder boxer engine that is iconic to the Subaru brand. The “BRAT” designation referred to its ability to carry two passengers in the rear “jump seats,” which were originally marketed as optional cargo covers but were technically recognized as seating areas in the United States. This unique configuration allowed the vehicle to be registered as a car for tax purposes while maintaining the utility of a light truck.
During the 1980s, Subaru was carving out a niche as a pioneer in all-wheel-drive technology. The BRAT offered the ruggedness of a truck with the handling and fuel efficiency typical of a compact car. The EA81 engine was known for its durability and simplicity, making it a favorite among off-road enthusiasts and those living in areas with harsh weather. The vehicle’s boxer engine layout provided a low center of gravity, which improved stability on rough terrain and snowy roads. The BRAT was essentially a compact wagon with a rear cargo bed, distinguishing it from the more conventional station wagons of the era. Its design allowed owners to haul small loads in the bed while enjoying the safety features of Subaru’s Symmetrical All-Wheel Drive system.
Despite its robust reputation, the 1987 BRAT is susceptible to specific issues that owners should be aware of. Over time, the EA81 engine can develop oil consumption issues, often due to worn piston rings or valve stem seals. Using a high-mileage synthetic oil designed to reduce sludge and enhance sealing properties can help mitigate these consumption problems and maintain compression. Another common issue involves the head gaskets, which can be prone to failure in high-mileage examples, leading to coolant leaks or overheating. High-quality Antifreeze & Coolant and proper flushing procedures are essential to prevent corrosion and ensure the cooling system remains efficient.
Furthermore, the transmission and transfer case systems in these older All-Wheel Drive vehicles can suffer from fluid degradation over time, leading to shifting issues or premature wear in the gear sets. Synthetic gear lubes are particularly beneficial here, as they resist thermal breakdown better than conventional oils, helping to protect the gears and synchronizers. Lastly, the electrical system, including the alternator and starter, can sometimes suffer from corrosion or poor connections due to age. While fluid maintenance won’t fix electrical gremlins directly, keeping the battery terminals and chassis grounded clean with anti-corrosion sprays can prevent voltage drops and starting issues. Regular maintenance with the right lubricants ensures that the 1987 Subaru BRAT continues to perform reliably, honoring its legacy as a versatile and capable vehicle.
Maintenance Summary
Performing a complete fluid maintenance regimen on your 1987 Subaru BRAT involves more than just changing the oil. It requires a holistic view of the vehicle’s lubrication needs, from the engine to the differential. For the engine, the 4.4-quart capacity is best served by AMSOIL Signature Series 10W-30 100% Synthetic Motor Oil or Extended-Life 10W-30 synthetic motor oil, depending on your desired service interval and cleaning requirements. Pairing this with an AMSOIL Oil Filter or WIX Oil Filter ensures that contaminants are removed efficiently, protecting the engine’s internal components. The transmission fluid change should utilize the specific synthetic automatic or manual transmission fluids recommended for the TX86 or GL-5 gear specifications, ensuring smooth shifting and reduced wear.
Coolant replacement is another vital step, with a capacity of 6.3 quarts for the radiator. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant provides a ready-to-use solution that prevents corrosion and freezing, while the Propylene Glycol option offers a concentrated alternative. For the differential and transfer case, using AMSOIL SEVERE GEAR® 80W-90 100% Synthetic Gear Lube or SEVERE GEAR® 75W-90 100% Synthetic Gear Lube is highly recommended, as it offers superior protection against wear and thermal runaway. Finally, the DOT 3 and DOT 4 100% Synthetic Brake Fluid should be a DOT 3 or DOT 4 synthetic fluid to ensure consistent stopping power and ABS responsiveness, even in extreme temperatures. By adhering to these specific lubrication recommendations, you can ensure that your 1987 Subaru BRAT remains in top condition for years to come.
Additional Protection Products
Beyond the essential fluid changes, there are several additional products that can enhance the performance and longevity of your Subaru BRAT. AMSOIL Gasoline Stabilizer is an excellent choice for seasonal storage, helping to keep fuel fresh for up to 12 months and preventing varnish and gum buildup caused by ethanol corrosion. For vehicles that sit for extended periods, AMSOIL Engine Fogging Oil can be used to coat internal engine components, protecting them from rust and corrosion during storage. To improve fuel economy and restore horsepower, AMSOIL P.i.® Performance Improver Gasoline Additive can be added to your fuel tank, helping to clean fuel injectors and control pre-ignition knock.
Maintenance of the vehicle’s exterior and undercarriage is also important, especially for an All-Wheel Drive vehicle that may see wet or snowy conditions. AMSOIL Heavy-Duty Metal Protector can be sprayed on exposed metal surfaces to provide a long-lasting, protective coating against rust and corrosion from salt and moisture. For routine cleaning, AMSOIL Miracle Wash Waterless Wash and Wax Spray offers a convenient way to clean and protect the paint without water, while AMSOIL Silicone Spray can be used on rubber components to prevent cracking and drying. Regular use of these ancillary products, combined with the recommended lubricants, ensures that your 1987 Subaru BRAT is protected inside and out.
In conclusion, maintaining a 1987 Subaru BRAT requires a thoughtful approach to lubrication that addresses the specific needs of its EA81 engine, transmission, and other mechanical components. By selecting high-quality synthetic fluids and following the recommended capacities and service intervals, owners can ensure that their vehicle continues to deliver the reliable performance and durability that the BRAT is famous for. Whether you are driving it on local roads or tackling off-road trails, the right lubricants will help your Subaru BRAT stand the test of time.