Ensuring your 2018 Mercedes-Benz SLC300 runs smoothly requires more than just following a standard maintenance schedule; it demands using fluids specifically designed to meet the rigorous engineering standards of European vehicles. The SLC300 is powered by the Mercedes 274.920 0 turbocharged 2.0-liter four-cylinder engine, a compact powerhouse that operates under significant stress. To maintain peak performance, protect internal components from wear, and ensure longevity, using the correct viscosity and chemical formulation is essential. This guide details the precise lubrication requirements for this vehicle, offering a comprehensive breakdown of the necessary fluids and the best AMSOIL synthetic options to keep your roadster in top condition.
Recommended AMSOIL Products
Based on the specific needs of the 2018 Mercedes-Benz SLC300 and its turbocharged engine, here are the primary lubrication recommendations. These products are formulated to exceed original equipment manufacturer requirements, offering superior protection against high temperatures, sludge, and wear.
- AMSOIL 5W-40 FS 100% Synthetic European Motor Oil – This European-specific formula features a precise blend of synthetic base oils and premium additives designed for the unique demands of gasoline and diesel vehicles. It provides excellent protection for the turbocharger and high-stress components.
- AMSOIL 0W-40 FS 100% Synthetic European Motor Oil – An excellent alternative viscosity choice for the same vehicle, offering exceptional flow at cold start temperatures while maintaining robust protection and film strength at operating heat.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – This unique OAT formulation provides protection up to 150,000 miles or 5 years. It is a 50/50 pre-mix that is safe for all cooling system metals, gaskets, and hoses, and is free of phosphates, nitrates, and silicates.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated, high-temperature stable coolant that requires mixing with distilled water. It offers extended service intervals and great corrosion protection for long-term engine health.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Designed for excellent ABS and traction-control responsiveness, this fluid maintains stable viscosity across a wide temperature range, ensuring consistent braking performance in all conditions.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – This fluid reduces friction and helps seals remain soft to prevent leaks. It resists heat for long fluid life and provides strong anti-wear protection for quiet operation.
Engine Oil and Filter Specifications
The heart of the SLC300 is the 2.0L 4-cylinder turbo engine, identified by code 274.920 0. This engine operates at higher temperatures and pressures than naturally aspirated engines due to the forced induction. Consequently, the motor oil must maintain stability and provide a strong lubricating film even under severe service conditions. For this vehicle, the recommended oil grades are 5W-30 or 5W-40, with 5W-40 being particularly effective for temperatures above -25°C. The engine oil capacity is 6.7 quarts when performing a change with a filter replacement.
When draining the oil, it is critical to adhere to the manufacturer’s torque specification of 30 ft/lbs for the oil drain plug. After refilling, always check the oil level to ensure it is within the correct range. While the source documentation notes that no specific oil filters are listed in the current database for this vehicle, using high-quality synthetic oil like the AMSOIL 5W-40 FS or 0W-40 FS European Motor Oils ensures that the oil itself provides maximum cleaning and protection, reducing the likelihood of sludge buildup and deposits common in turbocharged engines.
AMSOIL‘s European-specific oils are engineered to meet the exacting standards of Mercedes-Benz, featuring precise blends that protect against the high thermal loads of the turbocharger. These oils help extend the service intervals, allowing drivers to maximize the time between changes while maintaining superior engine cleanliness and extreme temperature performance.
Cooling System and Fluid Capacities
A healthy cooling system is vital for the longevity of a turbocharged engine. The 2018 SLC300 requires specific antifreeze formulations to prevent corrosion and boiling or freezing under extreme conditions. The capacity for the cooling system varies depending on the type of antifreeze used. For standard ethylene glycol-based coolants, the capacity is LTCC2 quarts. For high-temperature concentrated coolants like the AMSOIL Propylene Glycol, the capacity is noted as HTCC10 quarts.
It is important to use a compatible antifreeze that is phosphate-, nitrate-, nitrite-, silicate-, borate-, and amine-free to protect the various metals and seals within the cooling system. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a pre-mixed, 50/50 formulation that offers protection up to 150,000 miles or five years, eliminating the need for mixing and ensuring immediate protection upon installation.
Brake and Steering Fluid Requirements
Braking performance and steering precision are paramount for a vehicle like the SLC300. For the braking system, the manufacturer recommends using DOT 4 Plus fluids, specifically identifying part numbers 0009895605090109 (previously 0009895605110111) or 000989080701. Alternatively, any product approved on MB Sheet 331.0 is acceptable. AMSOIL’s DOT 3 and DOT 4 100% Synthetic Brake Fluid meets these strict standards, offering a higher boiling point and better stability than conventional glycol-based fluids. This results in improved pedal feel and reduced risk of brake fade during spirited driving.
The power steering system also benefits from synthetic lubrication. The recommended fluid for the SLC300’s power steering system is designated as PS031. AMSOIL’s 100% Synthetic Multi-Vehicle Power Steering Fluid is compatible with this requirement. It helps keep seals soft to prevent leaks, a common issue in older vehicles, and provides excellent high-temperature protection that resists breakdown and viscosity loss, ensuring quiet and smooth steering operation.
Additional Maintenance and Care
For owners who drive their SLC300 in severe conditions, during seasonal storage, or who wish to maximize fuel economy and engine efficiency, additional products can be highly beneficial. The AMSOIL P.i.® Performance Improver is an excellent gasoline additive that helps clean GDI fuel injectors, restores horsepower, and controls pre-ignition knock. For seasonal storage, AMSOIL Gasoline Stabilizer can keep fuel fresh for up to 12 months, preventing varnish and gum buildup, while the Engine Fogging Oil protects internal components from rust during long periods of inactivity.
Regular cleaning of the engine bay and vehicle surfaces is also part of maintaining a high-performance vehicle. Products such as the AMSOIL Heavy-Duty Degreaser can remove stubborn grime from the engine compartment, while the AMSOIL Glass Cleaner and Exterior Ceramic Spray help maintain the vehicle’s pristine appearance. Using these specialized fluids ensures that every aspect of the vehicle is cared for with high-quality lubricants that stand the test of time.
About the Vehicle: 2018 Mercedes-Benz SLC300
The 2018 Mercedes-Benz SLC300 represents a distinct chapter in the history of the brand’s roadster lineup. It serves as the successor to the iconic SLK class, rebranded to align with Mercedes-Benz’s “S-Class” luxury naming convention for its two-seater models. The SLC300 is built on a platform that prioritizes a blend of everyday usability and spirited performance, making it a favorite among enthusiasts who value both style and substance.
Powered by the Mercedes-AMG M274 engine, the SLC300 features a 2.0-liter inline-four cylinder engine equipped with a turbocharger and variable valve timing. This engine produces approximately 241 horsepower, delivering a robust power output that belies its displacement. The four-cylinder configuration allows the car to remain relatively agile and compact while still offering the refinement expected from a German luxury marque. The vehicle typically features a sleek, aerodynamic design with a retractable hardtop, which can stow away in about 20 seconds, transforming the roadster into a coupe for better rigidity and reduced wind noise.
Owners of the SLC300 often appreciate its balance of luxury and sportiness. It offers a comfortable interior with high-quality materials, modern infotainment systems, and a chassis that provides sharp handling characteristics. The car is particularly popular for its compact size, making it easy to park and maneuver in urban environments, while still offering enough room for a trunk and passengers. However, like any high-performance vehicle, the SLC300 faces certain challenges as it ages.
One common issue for this specific model involves oil consumption and potential sludge buildup in the turbocharger. The high operating temperatures of the turbo can lead to carbon accumulation and oil degradation if synthetic lubricants are not used regularly. Using a high-quality synthetic motor oil helps mitigate these issues by providing better thermal stability and cleaning properties. Another potential problem is the degradation of rubber seals in the cooling system and power steering components, which can lead to leaks. Synthetic brake and power steering fluids resist heat and oxidation better than standard fluids, helping to keep these seals pliable and functional for longer.
Additionally, owners may encounter issues with fuel injector clogging, particularly with the direct injection system, which can lead to reduced fuel economy and rough idling. Regular use of fuel system cleaners and high-quality fuel additives can help maintain injector flow and engine performance. Finally, the hardtop mechanism, while robust, relies on various seals and components that can wear over time; while not directly a lubrication issue, ensuring the vehicle is stored properly and the fluids are fresh can prevent stress on these mechanical systems. By choosing the right AMSOIL synthetic products, owners can proactively address these known areas of concern, ensuring their 2018 SLC300 remains a reliable and enjoyable driving companion for years to come.