The 2018 Mercedes-Benz CLS63 AMG S is a high-performance grand tourer that demands a different approach to maintenance than a standard luxury sedan. Powered by the formidable 5.5-liter twin-turbo V8, this vehicle pushes engine components to their thermal and mechanical limits, making the quality of lubricants a critical factor in longevity. Using fluids specifically formulated for these严苛 demands can significantly reduce wear, maintain performance, and protect the complex engineering inside the engine bay and drivetrain. Whether you are a weekend driver or a track enthusiast, the correct lubrication regimen ensures that every component, from the turbochargers to the automatic transmission fluid and brake fluid, operates with precision.
Recommended AMSOIL Products
- AMSOIL 5W-40 FS 100% Synthetic European Motor Oil – A premium synthetic specifically designed for the unique demands of gasoline, diesel, and hybrid European vehicles, featuring a precise blend of base oils and additives.
- AMSOIL 0W-40 FS 100% Synthetic European Motor Oil – Offers optimal flow for extreme cold starts while maintaining robust protection at high operating temperatures, tailored for European specifications.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – An extended-life, ethylene glycol 50/50 pre-mix formulation that protects all cooling system metals and exceeds original equipment manufacturer requirements for up to 150,000 miles.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated coolant that provides protection up to 150,000 miles in passenger cars and surpasses standards for metallic corrosion and erosion.
- AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Withstands the rigors of heavy towing, elevated temperatures, and challenging terrain while remaining fluid in sub-zero conditions.
- AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Designed to protect against wear and provide fuel efficiency, meeting the specific requirements of modern automatic transmissions.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent ABS and traction-control responsiveness with stable viscosity over a wide temperature range for superior stopping power.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – Helps seals remain soft to prevent leaks, resists heat for long fluid life, and provides strong anti-wear protection for quiet operation.
Maintaining the 2018 Mercedes-Benz CLS63 AMG S involves more than just topping off fluids; it requires a comprehensive understanding of the vehicle’s specific lubrication needs. The engine, a 5.5L 8-cylinder Turbo (Engine Code 157.98 6), requires a substantial oil capacity of 9 quarts including the filter. This volume is critical because the complex oiling system of the twin-turbo V8 must be flooded adequately to ensure all bearings and the turbocharger shafts receive consistent lubrication. The recommended viscosity grades include 0W-30, 0W-40 for all temperatures, and 5W-30 or 5W-40 for conditions above -25°C. It is essential to check the oil level after the refill and adhere to the specified torque settings for the drain plug, which varies between plastic, M12 bolt, and M14 bolt options to ensure a leak-free seal without damaging the pan.
The cooling system is equally critical for a vehicle of this caliber. The High-Temperature Coolant Capacity (HTCC) is 9 quarts, while the Low-Temperature Coolant Capacity (LTCC) is 2.5 quarts. Selecting the right coolant is vital for managing the intense heat generated by the supercharged powerplant. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant offers a poly-organic acid (OAT) formulation that is phosphate-, nitrate-, nitrite-, silicate-, borate-, and amine-free, making it compatible with all other antifreeze colors and safe for all cooling system metals and hoses. Alternatively, the Propylene Glycol Antifreeze provides a concentrated option that requires mixing with distilled water, offering protection up to 150,000 miles or 5 years.
Transmission and Drivetrain Protection
The transmission in the CLS63 AMG S, specifically the 722.971 variant, requires careful attention to fluid selection based on the vehicle’s data card code. If the vehicle is equipped with the A89 code (Reduced-Friction), or the SL058 specification, it needs a specific fluid to ensure proper operation. Conversely, without the A89 code (SL057), the requirements may differ slightly. In either case, the total fill capacity for the 7-speed transmission is 8.2 quarts. Using a fluid like AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid ensures that the transmission withstands the heavy loads and elevated temperatures typical of AMG performance driving. The fluid remains fluid in sub-zero temperatures and provides reserve protection during heavy use, preventing wear and sludge buildup that can lead to costly failures.
While the CLS63 AMG S does not use a transfer case in the traditional four-wheel-drive sense, the differential lubrication is handled with similar high-performance standards. The front differential capacity is 1.3 pints, and the rear requires 2.5 pints. Although specific differential fluids were not detailed in the primary source text, ensuring that any fluids used for drivetrain components meet the rigorous standards of the AMG lineup is essential for maintaining the sharp handling characteristics that define the CLS63 S. The power steering fluid, designated PS031, benefits from a synthetic formula that reduces friction and helps seals remain soft, preventing leaks that could compromise steering feel and system pressure.
Brake performance is non-negotiable for a vehicle with this much power. The CLS63 AMG S requires a DOT 4 plus, specifically meeting MB Sheet 331.0 standards or using products approved with codes like 0009895605090109. AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid is an excellent choice, offering stable viscosity and excellent responsiveness for the anti-lock braking and traction control systems. This ensures that the brakes provide consistent stopping power regardless of how hard the engine pushes the car, giving the driver confidence in the stopping distance and modulation.
About the Vehicle
The 2018 Mercedes-Benz CLS63 AMG S represents the pinnacle of the brand’s “four-door coupe” philosophy, blending the sleek, sloping lines of a sports car with the practicality of a luxury sedan. This vehicle is built on the MRA (Mercedes Rear Architecture) platform, which was engineered to offer a lower center of gravity and improved weight distribution, enhancing handling dynamics significantly compared to its predecessors. Under the hood lies the handcrafted M177 engine, a 4.0-liter twin-turbo V8, though the CLS63 S model in this era often refers to the culmination of the M157 lineage in certain configurations before the full transition, delivering approximately 603 horsepower and 627 lb-ft of torque. This immense power allows the vehicle to accelerate from 0 to 60 mph in just 3.4 seconds, rivaling many dedicated sports cars while offering a level of comfort and refinement typical of high-end Mercedes-Benz models.
The CLS63 AMG S was designed for drivers who demand performance without compromising on daily usability. It features an aggressive aesthetic with a prominent grille, wide wheel arches, and aerodynamic enhancements that not only look stunning but also manage airflow to cool the twin turbochargers. The interior is equally luxurious, often featuring Nappa leather, wood trim, and advanced MBUX technology (in later updates) or COMAND systems that provide a connected and intuitive driving experience. The suspension system, typically the AMG RIDE CONTROL sports suspension, allows drivers to switch between a comfortable touring mode and a firm, sporty mode, adapting to both city streets and winding backroads with ease.
However, the pursuit of such high performance comes with specific challenges for the vehicle’s maintenance. Owners of the CLS63 AMG S often report issues related to carbon buildup on intake valves due to the direct injection system, a common trait in modern high-output engines. The use of high-quality synthetic oils and AMSOIL P.i.® Performance Improver Gasoline Additive can help mitigate the formation of carbon deposits, ensuring that the engine remains clean and efficient over time. Additionally, the heat management requirements are significant; the cooling system must be robust enough to handle sustained high-speed driving without boiling, which underscores the importance of using extended-life coolants like the ones recommended.
Another common area of concern for this model is the high-voltage system and the complex electronic controls that manage the transmission and engine tuning. Ensuring that all fluid systems are functioning perfectly reduces the load on these electronic systems to manage thermal issues. Some owners have also noted issues with the exhaust flaps and the turbochargers themselves, which can fail if oil degradation occurs due to extended intervals or the use of inferior lubricants. The turbochargers in this vehicle spin at incredibly high speeds, making the initial cold-start protection and the stability of the oil film at operating temperature paramount. Using a synthetic European motor oil formulated for these demands provides the necessary protection to keep the turbos running smoothly and to extend the life of the high-value components.
The CLS63 AMG S has garnered a reputation as one of the best performance sedans available, offering a unique balance of speed, style, and luxury. It stands out in the market as a vehicle that does not compromise on any front, whether that is straight-line acceleration, cornering agility, or the plushness of the ride. For owners who wish to maintain this level of performance, selecting the correct fluids is not just a maintenance task but an investment in the vehicle’s future. By adhering to the recommended lubrication guidelines and using products like those from AMSOIL, owners can ensure that their CLS63 AMG S continues to deliver the thrilling driving experience it was designed for, year after year.