Maintaining the 2012 Infiniti FX50 with a 5.0L V8 engine requires precise fluid selection to handle the unique demands of its high-performance powerplant. Whether you are towing heavy loads, navigating steep mountain roads, or enduring extreme winter temperatures, the correct lubricants ensure that every moving part receives optimal protection against wear. The FX50’s VK50VE engine is a masterpiece of engineering, but it demands top-tier synthetic solutions to maximize its potential and longevity. Using the wrong viscosity or a standard mineral oil can lead to premature wear, reduced fuel economy, and costly repairs. This guide details the exact fluid capacities and product recommendations needed to keep your luxury SUV running smoothly for the long haul.
Recommended AMSOIL Products
- AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil – Offers the highest level of engine protection with up to 25,000 miles of service life, ideal for high-output engines.
- AMSOIL Extended-Life 5W-30 100% Synthetic Motor Oil – Provides 37% more cleaning power to keep the engine running smoothly for up to 20,000 miles.
- AMSOIL Oil Filter – Delivers 99% filtration efficiency at 20 microns to trap harmful contaminants and extend engine life.
- WIX Oil Filter – A premium alternative featuring advanced media that exceeds OEM filtration standards.
- AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Resists thermal breakdown during heavy towing and ensures smooth shifting in all conditions.
- AMSOIL SEVERE GEAR® 75W-90 100% Synthetic Gear Lube – Essential for the rear differential, providing advanced wear protection and resistance to thermal runaway.
The heart of the 2012 FX50 is the 5.0-liter naturally aspirated V8 engine, code-named VK50VE. This powerplant is known for its robust construction and smooth power delivery, but it requires a significant volume of oil to function correctly. The capacity for a standard oil change, including the filter replacement, is 7.1 quarts. Using a high-quality 5W-30 synthetic motor oil is the primary recommendation for this engine. While there are several grades available, such as the OE series for those seeking OEM-equivalent performance, the Signature Series stands out for its superior protection against horsepower loss and wear. It is formulated to handle the high stresses placed on the engine, particularly in performance driving scenarios. For vehicles with over 75,000 miles, the High-Mileage 5W-30 variant offers a unique chemistry designed to boost detergency and reduce sludge, helping older engines maintain peak performance.
Transmission and Drivetrain Fluids
The automatic transmission in the FX50, specifically the 7-speed RE7R01B, operates under substantial load and heat, especially when navigating the varied terrain that SUV owners often encounter. Maintaining the fluid integrity here is crucial for preventing shudder and ensuring crisp gear changes. AMSOIL offers a range of transmission fluids tailored for this application. The Signature Series Fuel-Efficient Automatic Transmission Fluid is an excellent choice for those who want to extract every ounce of performance from the drivetrain while resisting the rigors of heavy towing and elevated temperatures. It remains fluid even in sub-zero conditions, ensuring reliable starts and smooth operation. For a cost-effective solution that still offers 100% synthetic protection, the OE Fuel-Efficient variant provides a robust barrier against wear and sludge, extending the life of the transmission components.
The transfer case and differentials also benefit from specialized lubrication. The transfer case requires approximately 2.1 pints of fluid, while the front differential (F160A) needs 1.4 pints. Both front and rear differentials are compatible with synthetic gear lubricants that offer superior thermal stability compared to conventional oils. The AMSOIL SEVERE GEAR® line is engineered to handle the extreme pressures found in gear systems. The 75W-90 viscosity is specifically recommended for the rear differential, which holds 3.7 pints. This lube contains friction modifiers suitable for limited-slip differentials, preventing chatter and providing a smooth ride. The 80W-90 grade is an alternative for certain temperature ranges, offering long oil and seal life while protecting against rust and corrosion. By using these premium synthetic gear lubes, you help control operating temperatures and extend the life of seals and gears.
Essential Cooling and Brake Systems
A robust cooling system is vital for the longevity of the VK50VE engine. The 2012 FX50 requires 11.6 quarts of Antifreeze & Coolant to fill the system completely. AMSOIL’s Passenger Car & Light Truck Antifreeze & Coolant is a ready-to-use, 50/50 pre-mix formulation that offers protection for up to 150,000 miles or five years. It is phosphate-, nitrate-, and silicate-free, ensuring compatibility with all metal components in the cooling system without causing corrosion. For those who prefer concentrated coolant, the Propylene Glycol option allows for customization but requires mixing with distilled water. Both options provide excellent freeze and boil-over protection, keeping the engine at its optimal operating temperature regardless of the weather conditions.
Brake fluid is another critical fluid that is often overlooked. The FX50 utilizes a DOT 3 hydraulic brake fluid system. AMSOIL’s DOT 3 and DOT 4 100% Synthetic Brake Fluid offers superior performance over conventional fluids by maintaining stable viscosity across a wide temperature range. This stability ensures responsive ABS and traction-control systems, providing confidence in emergency stopping situations. Additionally, the power steering system benefits from AMSOIL’s 100% Synthetic Multi-Vehicle Power Steering Fluid. This fluid reduces friction and helps seals remain soft to prevent leaks, ensuring quiet operation and consistent steering feel. It offers strong anti-wear protection and resists heat degradation, making it ideal for the high demands placed on the steering rack.
Vehicle Background
The 2012 Infiniti FX50 represents the pinnacle of the FX crossover line during its production era. Built on the same platform as the Nissan GT-R but tailored for luxury and versatility, the FX50 is a unique blend of sport sedan dynamics and SUV practicality. Its defining feature is the 5.0L VK50VE V8 engine, which produces an estimated 390 horsepower, delivering a thrilling driving experience that was rare in the crossover segment at the time. The vehicle’s design, characterized by a sloping roofline and muscular stance, made it stand out on the road, often drawing comparisons to exotic sports cars despite its SUV status.
Owners of the FX50 often appreciate its rear-wheel-drive bias, which provides a more engaging driving character than typical front-wheel-drive crossovers. The 7-speed automatic transmission is known for its quick response times, and the suspension tuning offers a balance between comfort and handling agility. While the FX50 was discontinued after the 2013 model year in the US, the vehicle has garnered a loyal following for its build quality and performance potential. It is a vehicle that demands high-quality maintenance to preserve its original driving dynamics. The VK50VE engine is known for its durability, but like any high-performance powerplant, it benefits significantly from the use of premium synthetic lubricants that can withstand the heat and stress of spirited driving. By adhering to the recommended fluid specifications and utilizing AMSOIL’s synthetic products, owners can ensure that their FX50 continues to deliver the performance and luxury experience it was designed to provide.
Additional Maintenance and Protection
Beyond the core engine and drivetrain fluids, regular maintenance of the 2012 FX50 includes attention to air filtration and fuel system health. The WIX Air Filter is recommended to ensure the engine breathes cleanly, improving performance and fuel efficiency. For seasonal storage, AMSOIL offers a Gasoline Stabilizer to keep fuel fresh for up to 12 months, protecting against varnish and gum buildup that can clog fuel injectors. The P.i. Performance Improver is another valuable tool for maintaining fuel system cleanliness, restoring up to 14% horsepower and ensuring that GDI injectors flow at 100%. These additives work synergistically with synthetic oils to provide a comprehensive protection package for the vehicle. Whether you are a performance enthusiast or a family driver, using these specialized fluids and additives ensures that your 2012 Infiniti FX50 remains in top condition.
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