The 2018 Mercedes-Benz AMG GT S is a high-performance sports car designed for those who demand the pinnacle of driving dynamics. Under the hood lies the potent 4.0-liter twin-turbo V8 engine, a masterpiece of German engineering that requires precise lubrication to maintain its power and longevity. This engine, with its unique combustion characteristics and high thermal loads, operates best with synthetic lubricants formulated to meet the rigorous demands of European performance vehicles. Using the correct fluids is not merely a maintenance task; it is a critical component of preserving the vehicle’s aggressive performance profile and protecting expensive internal components from premature wear.
Recommended AMSOIL Products
For the 2018 Mercedes-Benz AMG GT S, AMSOIL offers specific formulations designed to meet or exceed the manufacturer’s stringent requirements. The following products are recommended for this vehicle:
- AMSOIL 5W-40 FS 100% Synthetic European Motor Oil – Engineered for the unique demands of gasoline and diesel European vehicles, featuring a precise blend of synthetic base oils and premium additives to handle high temperatures and turbocharger stress.
- AMSOIL 0W-40 FS 100% Synthetic European Motor Oil – Provides superior cold-start protection while maintaining viscosity at high operating temperatures, ideal for all weather conditions in high-performance engines.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A unique poly-organic acid formulation that provides protection up to 150,000 miles or 5 years, safeguarding all cooling system metals and components against corrosion.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated coolant that requires mixing with distilled water, offering extended protection up to 150,000 miles or 5 years in passenger cars and light trucks.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent responsiveness for ABS and traction control systems with a stable viscosity across a wide temperature range, ensuring consistent braking performance.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – Formulated for quiet operation, it reduces friction and helps seals remain soft to prevent leaks while resisting heat for extended fluid life.
Engine Oil Specifications and Capacities
The heart of the 2018 AMG GT S is the 4.0-liter V8 engine (Engine Code 178.980 D Turbo). This powerplant operates under extreme conditions, generating significant heat and requiring constant lubrication to the high-RPM pistons, bearings, and the twin turbochargers. The manufacturer specifies a viscosity grade of 0W-40 or 5W-40 for all temperature ranges. For a complete oil change including the oil filter, the system requires 7.4 quarts of fluid. After refilling, it is crucial to check the oil level to ensure it is within the optimal operating range. When reinstalling the oil drain plug, ensure it is torqued to 22 ft/lbs to prevent leaks or damage to the plug threads. Both AMSOIL 5W-40 FS and 0W-40 FS European Motor Oils are designed specifically for these European performance engines, offering superior protection against the high-velocity shear forces and thermal breakdown associated with turbocharged applications.
Cooling System Maintenance
Efficient cooling is vital for the longevity of the AMG GT S’s engine. The cooling system has a substantial capacity of 15 quarts. AMSOIL offers two primary options for this system. The Passenger Car & Light Truck Antifreeze & Coolant is a 50/50 pre-mix formulation that is phosphate-, nitrate-, nitrite-, silicate-, borate-, and amine-free, ensuring compatibility with all other antifreeze colors and protecting various cooling system metals, gaskets, and hoses. For those preferring to mix their own, the Propylene Glycol Antifreeze and Engine Coolant provides a concentrated solution that must be mixed with distilled or high-quality water. Both formulations are engineered to exceed original equipment manufacturer (OEM) requirements and offer protection for up to 150,000 miles or 5 years.
Brake and Power Steering Fluids
The braking system on a vehicle like the AMG GT S demands absolute reliability and consistent performance. The recommended fluid is a DOT 4 plus equivalent, meeting MB Sheet 331.0 specifications. AMSOIL’s DOT 3 and DOT 4 100% Synthetic Brake Fluid provides a stable viscosity over a wide temperature range, ensuring the ABS and traction control systems respond instantly. Additionally, the vehicle utilizes a power steering system that benefits from a high-quality synthetic fluid. AMSOIL’s 100% Synthetic Multi-Vehicle Power Steering Fluid reduces friction and protects against heat, ensuring the system operates quietly and efficiently for the long haul.
Vehicle Background and Performance Profile
The 2018 Mercedes-Benz AMG GT S is a flagship model in the high-performance sports car segment, representing the pinnacle of the AMG line’s capabilities before the introduction of the later GT Black Series and GT R models in subsequent years. Born from the collaboration between Mercedes-Benz and HWA GmbH, the AMG GT platform was designed to challenge the established leaders in the supercar market, offering a more accessible entry point into high-performance driving while retaining the aggressive styling and engineering excellence expected from the brand. The “S” designation denotes a mid-tier power upgrade over the base GT model, featuring a handcrafted 4.0-liter V8 biturbo engine that delivers approximately 515 horsepower.
Driving the AMG GT S is an experience defined by raw power and precise handling. The low-slung chassis and rear-wheel-drive layout provide a communicative road feel that allows drivers to push the car to its limits on track days or twisty mountain roads. The twin-turbo V8 engine is renowned for its linear power delivery and rapid acceleration, though the intense heat generated by this powertrain places significant stress on all fluid systems. The vehicle’s reputation as a daily-drivable supercar means it sees a wide variety of conditions, from short city commutes to long highway stretches, making fluid stability and longevity critical factors for owners who want to maintain performance and reliability.
Despite its robust engineering, the AMG GT S has specific maintenance requirements that owners must address to avoid common issues associated with high-performance vehicles. One known challenge involves oil consumption or leaks at the valve cover gaskets, which can be exacerbated by the high thermal cycling the engine undergoes. Using high-quality synthetic motor oils like AMSOIL FS, which are formulated to resist thermal breakdown and maintain a protective film on critical components, can help mitigate these risks and extend the intervals between seal replacements. Another area of concern for some owners is the potential for carbon buildup on the intake valves and fuel injectors, particularly given the direct injection nature of the engine. AMSOIL P.i.® Performance Improver is designed to clean the fuel system and restore injectors to 100% flow rate, helping to maintain the engine’s rated horsepower and smooth operation. Additionally, the high temperatures generated by the turbochargers and transmission can sometimes lead to fluid degradation, where traditional fluids may break down faster than expected. Switching to premium synthetic fluids that offer extended service life can provide a buffer against this wear, ensuring that the transmission and cooling systems remain protected even under severe driving conditions. Finally, brake fade can become an issue during spirited driving; high-performance synthetic brake fluids with higher boiling points help maintain consistent pedal feel and prevent the loss of braking power when the system is heated to extreme temperatures.