Maintaining the peak performance of your 2022 Mercedes-Benz CLS450 begins with selecting the right lubricants for its sophisticated engineering. This vehicle houses a 3.0L 6-cylinder turbocharged engine (Engine Code 256.930) that demands precise fluid specifications to handle the stress of high performance, extreme temperatures, and modern emissions systems. Using manufacturer-specified fluids ensures that the turbocharger, variable valve timing components, and intricate cooling systems operate within optimal parameters, extending the lifespan of the powertrain and maintaining the vehicle’s smooth driving character. Proper fluid selection also protects against the specific challenges of German luxury performance sedans, such as high thermal loads and strict warranty requirements.
Recommended AMSOIL Products
- AMSOIL 5W-30 LS 100% Synthetic European Motor Oil – Specifically formulated with a precise blend of synthetic base oils and premium additives designed for the unique demands of gasoline, diesel, and hybrid European vehicles, ensuring excellent protection for your turbocharged engine.
- AMSOIL 5W-40 MS 100% Synthetic European Motor Oil – An excellent alternative viscosity option for this vehicle, offering the same European formula benefits with a precise blend to protect against wear and maintain flow in varying temperatures.
- AMSOIL 0W-20 LS 100% Synthetic European Motor Oil – Ideal for colder climates or applications requiring lower viscosity for maximum fuel efficiency, while still meeting the rigorous standards required for European luxury performance engines.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A unique poly-organic acid (OAT) formulation that protects all cooling system metals, gaskets, and hoses, offering protection up to 150,000 miles or 5 years.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated option that greatly surpasses standards for metallic corrosion and erosion, allowing for mixing with distilled water to create a highly efficient cooling solution.
- AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Designed to withstand heavy towing, elevated temperatures, and challenging terrain while remaining fluid in sub-zero temperatures, providing reserve protection during heavy use.
- AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – A cost-effective yet high-performance option that protects against wear and ensures smooth shifting characteristics for your automatic transmission.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Provides excellent ABS and traction-control responsiveness with a stable viscosity over a wide temperature range, ideal for the sensitive braking systems found in the CLS450.
Essential Engine Specifications and Capacities
Understanding the specific fluid requirements for the 2022 Mercedes-Benz CLS450 is crucial for optimal maintenance. The engine, identified by code 256.930, is a turbocharged 3.0L unit that operates under significant pressure and heat. For the crankcase, the manufacturer recommends a total capacity of 9 quarts when including a filter change. After refill, it is imperative to check the oil level to ensure the correct amount is present, as the oil pump and cooling efficiency rely heavily on precise levels.
While the engine oil capacity is standard, the cooling system requires a larger volume. The High Temperature coolant Circuit (HTCC) holds 12.7 quarts, while the Low Temperature coolant Circuit (LTCC) requires 3.2 quarts. These distinct circuits manage different thermal loads, necessitating a coolant that remains stable and protective across the board. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant and the Propylene Glycol Antifreeze are excellent choices here, as they are compatible with all other coolant colors and free of phosphates, nitrates, nitrites, silicates, borates, and amines, which can be harmful to certain European engine components over time.
The automatic transmission also benefits from synthetic protection. While specific capacities vary based on the exact transmission configuration, using a high-quality synthetic fluid helps manage the heat generated during spirited driving or towing. The Signature Series and OE Fuel-Efficient transmission fluids are designed to reduce friction, which can improve overall fuel economy and extend the service intervals between changes.
Protection for Braking and Drivetrain Components
Braking fluid in a high-performance sedan like the CLS450 must handle extreme heat and moisture without losing its effectiveness. AMSOIL DOT 3 and DOT 4 100% Synthetic brake fluid meets the necessary specifications, offering a stable viscosity that ensures consistent pedal feel and responsive ABS activation. This is particularly important for owners who track their vehicles or drive in stop-and-go traffic where brake temperatures can soar.
For the differential and transfer case, which may require specific lubricants depending on the drivetrain configuration, AMSOIL offers solutions that resist thermal degradation and oxidation. The transfer case capacity is listed at 1.5 pints, and ensuring the correct torque on the fill and drain plugs (10 ft/lbs and 18 ft/lbs respectively) is essential to prevent leaks. Synthetic lubricants in these components provide superior load-carrying capacity and shear stability, preventing the grease from squeezing out under high pressure or cold conditions.
Additionally, the use of fuel additives can play a significant role in maintaining engine cleanliness. Injectors on direct injection engines can accumulate carbon deposits over time, reducing power and efficiency. Products like the AMSOIL P.i.® Performance Improver are designed to restore fuel injectors to 100% flow rate and help prevent carbon buildup, ensuring that the turbocharger and engine receive the correct fuel mixture for optimal combustion.
About the Vehicle: 2022 Mercedes-Benz CLS450
The 2022 Mercedes-Benz CLS450 represents the pinnacle of “Sport Coupe” design, blending the sleek, four-door fastback silhouette of the S-Class with the dynamic handling of a sports car. This model sits in a unique market position, offering the luxury and refinement expected from the German automaker while providing a more athletic driving experience than the standard C-Class or E-Class sedans. The vehicle is built on the MRA platform, which allows for a low center of gravity and excellent weight distribution, contributing to its agile handling characteristics.
Under the hood, the CLS450 is powered by the M256 engine, a 3.0-liter inline-six that features a 48-volt mild-hybrid system known as EQ Boost. This technology integrates an electric supercharger and a belt-driven starter generator. The electric supercharger eliminates lag, spooling the turbocharger in milliseconds for instant torque, while the EQ Boost system provides an additional 21 horsepower and 184 lb-ft of torque for overtaking maneuvers and start-stop efficiency. This setup delivers a smooth, refined power delivery that is characteristic of modern AMG-influenced performance vehicles, making it a favorite among enthusiasts who appreciate both comfort and capability.
Despite its sophisticated engineering, the CLS450 is not without its known operational challenges, many of which can be mitigated with high-quality synthetic lubricants. One common issue in this era of Mercedes-Benz is carbon buildup on the intake valves, particularly in the direct injection system. While the EQ Boost helps, the high temperatures can still lead to fouling over time. Using a premium gasoline additive like the AMSOIL P.i.® can help keep these injectors and intake pathways clean, restoring performance and fuel economy.
Another area of concern for owners is the potential for coolant system issues, particularly with the plastic components used in the cooling circuits over time. The constant thermal cycling of the 3.0L engine can put stress on gaskets and hoses. A high-quality OAT coolant that is free of silicates and phosphates helps prevent corrosion and extends the life of these components, reducing the risk of overheating or leaks. Furthermore, the mild-hybrid battery system and associated wiring can be sensitive to extreme temperatures, making a stable engine coolant even more critical for the vehicle’s longevity.
Owners may also experience issues with transmission shift quality or the electric motor engagement in the EQ Boost system. While these are complex electronic and mechanical interactions, the use of a high-temperature stable transmission fluid can smooth out shifting events and protect the internal clutches from wear. Finally, brake fade can become an issue during aggressive driving on winding roads or track days. Synthetic brake fluid with a high boiling point ensures that the pedal remains firm even after repeated hard stops, providing the safety and confidence drivers expect from a luxury performance coupe.