The 1987 Ford Bronco II with the 2.9L 6-cylinder engine (Engine Code [T]) requires specific lubricants to maintain the health of its mechanical components. This compact SUV, originally designed for light truck duty, relies heavily on precise oil viscosity and high-quality filters to manage the friction and heat generated by its aging engine design. Over time, the 2.9L engine can suffer from oil degradation, sludge buildup, and increased wear in the cooling and transmission systems. Selecting the correct AMSOIL Signature Series synthetic fluid ensures that every moving part, from the piston rings to the transmission gears, receives the protection it needs to continue performing reliably on the road or off-road.
Recommended AMSOIL Products
- AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil – Provides the highest level of protection against horsepower loss and wear, capable of lasting up to 25,000 miles between changes.
- AMSOIL Extended-Life 5W-30 100% Synthetic Motor Oil – Delivers extended protection with up to 20,000 miles of coverage, offering enhanced cleaning power to keep the engine running smoother.
- AMSOIL OE 5W-30 100% Synthetic Motor Oil – An economical synthetic option that fights sludge and deposits while outperforming conventional oils and meeting OEM requirements.
- AMSOIL 5W-30 100% Synthetic High-Mileage Motor Oil – Specifically formulated for engines with over 75,000 miles to reduce oil consumption, leaks, and sludge.
- AMSOIL Oil Filter – Features a full-synthetic filter media for superior filtration, capturing small contaminants to reduce engine wear and extend service life.
- WIX Oil Filter – A premium aftermarket alternative that offers improved filtration over original equipment manufacturer filters.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A 50/50 pre-mix ethylene glycol coolant offering protection for up to 150,000 miles or 5 years.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated, non-ethylene glycol formula that provides superior corrosion protection and long service life.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Withstands heavy towing and extreme temperatures while remaining fluid in sub-zero conditions.
- AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Designed to resist sludge, protect against wear, and promote smooth, shudder-free shifts.
- AMSOIL Torque-Drive 100% Synthetic Automatic Transmission Fluid – Offers superior thermal and oxidative stability for extended fluid life and long-term performance.
- WIX Transmission Filter – Provides premium filtration to protect the automatic transmission from debris and sludge buildup.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent ABS responsiveness and a stable viscosity across a wide temperature range.
- AMSOIL SEVERE GEAR 80W-90 100% Synthetic Gear Lube – Advanced protection for differentials, containing friction modifiers ideal for limited-slip applications.
- AMSOIL SEVERE GEAR 75W-90 100% Synthetic Gear Lube – Controls thermal runaway and reduces operating temperatures in heavy-duty differential applications.
- AMSOIL SEVERE GEAR 75W-110 100% Synthetic Gear Lube – A heavier viscosity synthetic lube for extreme load conditions and limited-slip differentials.
- AMSOIL Super Shift Racing Transmission Fluid – An excellent choice for power steering systems, resisting extreme heat to eliminate slippage and improve performance.
Proper lubrication for your 1987 Ford Bronco II begins with the engine. This 2.9L inline-six engine, part of Ford’s Cologne V6 family (specifically the 2.9L “Cologne” variant), is a robust design but benefits significantly from synthetic lubricants. The manufacturer specified a capacity of 5.0 quarts for an oil change, including the filter. When performing this service, it is crucial to remove the dipstick during refilling to allow oil to flow freely into the crankcase, and to torque the drain plug to the specified 15-21 ft/lbs. Synthetic motor oil is particularly beneficial here because it resists thermal breakdown better than conventional oil, which is vital for a vehicle that may be used for towing or driving in varying climates. The AMSOIL Signature Series offers the best protection, while the AMSOIL OE option provides a balanced performance choice.
Engine Oil and Filter Recommendations
For the engine, AMSOIL Signature Series 5W-30 is the top-tier choice, offering unsurpassed protection for up to 25,000 miles. For those seeking a balance of performance and value, the AMSOIL OE 5W-30 is an excellent option that outperforms conventional oils while meeting original equipment mileage expectations. If your Bronco II has accumulated significant mileage, the AMSOIL 5W-30 High-Mileage Motor Oil is designed with a unique chemistry to help reduce oil consumption and sludge, while the Extended-Life option provides up to 20,000 miles of protection. Pairing any of these oils with the AMSOIL Oil Filter ensures that contaminants are trapped effectively, preventing them from circulating through the engine and causing wear. The filter’s synthetic media allows for lower restriction, keeping engine parts properly lubricated even at high RPMs. A WIX Oil Filter serves as a great alternative OEM-matching filter.
Transmission and Driveline Care
The 1987 Bronco II typically came with the A4LD automatic transmission, which is known for its durability but requires careful fluid maintenance to ensure smooth shifting. The total fill capacity for a 4-speed 4WD A4LD is 10 quarts, while the 4-speed RWD model takes 9 quarts for a total fill, with an initial fill of 3 quarts. AMSOIL provides several synthetic transmission fluids tailored for these requirements. The Signature Series Multi-Vehicle ATF is ideal for heavy towing and challenging terrain, while the OE Multi-Vehicle ATF offers excellent protection against sludge and shudder. For the transfer case, which on the Bronco II is often a Warner 1350, AMSOIL offers fuel-efficient synthetic fluids like the Signature Series Fuel-Efficient or the OE Fuel-Efficient that can also be used in manual transmissions. The differential lubrication is equally critical, with capacities varying by axle: the Dana 28 front requires 1.1 pints, the Dana 35 front takes 3.6 pints, and the rear GL-5 standard or limited-slip differentials require 5.1 pints. The AMSOIL SEVERE GEAR 80W-90, SEVERE GEAR 75W-90, and SEVERE GEAR 75W-110 products provide the necessary gear lube to handle the stress of off-road driving and towing, protecting against rust, corrosion, and thermal runaway.
Cooling and Brake Fluids
Maintaining the cooling system is essential for this vintage vehicle. The Bronco II holds 7.9 quarts of coolant with air conditioning and 7.4 quarts without it. Using AMSOIL Passenger Car & Light Truck Antifreeze & Coolant or the Propylene Glycol version ensures that the system remains free of corrosion and cavitation damage for up to 150,000 miles. For the braking system, AMSOIL DOT 3 and DOT 4 Synthetic Brake Fluid offers stable viscosity over a wide temperature range, ensuring consistent pedal feel and excellent ABS responsiveness, which helps maintain the safety of the vehicle.
About the Vehicle
The 1987 Ford Bronco II occupies a unique place in automotive history as a compact SUV built on the Pinto platform, specifically designed to bridge the gap between a standard sedan and a full-sized SUV like the Ford Bronco. While it was marketed as a rugged, off-road capable vehicle, its primary role was to serve as an agile, fuel-efficient alternative for consumers who needed some utility without the massive size and poor gas mileage of larger trucks. The 2.9L 6-cylinder engine was Ford’s attempt to provide adequate power and torque in a lightweight package, offering a balance that appealed to city drivers and light trail enthusiasts alike. It sits firmly in the category of “small SUVs,” offering higher ground clearance and four-wheel drive options that set it apart from standard passenger cars of the era.
Owners of the Bronco II often appreciate its simple mechanical layout and compact footprint, which made it easier to maneuver through tight city streets and narrow trails compared to larger SUVs. However, this simplicity and age bring specific challenges. One common issue with the Bronco II’s 2.9L engine is oil consumption and sludge buildup, particularly in older units that have not seen regular synthetic oil changes. The oil pumps and internal passages can become clogged over time, reducing oil pressure and leading to increased engine wear. Another prevalent problem involves the cooling system, where rust and corrosion can accumulate in the radiator and water jackets, potentially leading to overheating. High-quality synthetic antifreeze is crucial to prevent this degradation and protect the metal components. The automatic transmission is another area that requires attention; the A4LD transmission can become prone to shuddering and hard shifts if the fluid degrades or if the filter becomes clogged. Synthetic transmission fluids help maintain smooth shifting and extend the life of the clutch packs. Finally, the differentials and transfer case can suffer from wear and tear due to the high torque loads and off-road usage, often leading to noise and potential failure if not lubricated with the correct synthetic gear lube. Addressing these common issues with premium synthetic lubricants can significantly restore the vehicle’s performance and reliability.
The Bronco II also features a hydraulic brake system that relies on the integrity of the brake fluid. Over decades, brake fluid absorbs moisture, which lowers its boiling point and can lead to brake fade or corrosion in the master cylinder and calipers. A complete flush with synthetic brake fluid restores the system’s integrity. Additionally, the power steering system, which relies on transmission fluid in some configurations, benefits from the high heat resistance of AMSOIL Super Shift Racing Transmission Fluid, preventing the seals from hardening and reducing the likelihood of leaks. By addressing these specific wear points, owners can extend the life of their vehicle and keep it running smoothly.