Ensuring your 2021 Mercedes-Benz GLC63 AMG receives the correct lubricants is critical for maintaining the performance of its powerful 4.0L V8 twin-turbo engine. This high-performance vehicle operates under extreme thermal and mechanical stresses that standard fluids cannot withstand. Proper fluid maintenance protects the engine, transmission, and cooling system, ensuring longevity and peak power output for years to come.
Recommended AMSOIL Products
- AMSOIL 5W-40 FS 100% Synthetic European Motor Oil – Specifically engineered for the unique demands of European vehicles, featuring a precise blend of synthetic base oils and premium additives to handle turbocharged engines and high RPMs.
- AMSOIL 0W-40 FS 100% Synthetic European Motor Oil – Provides superior protection in extreme temperatures, ensuring instant lubrication during cold starts and maintaining viscosity during high-heat operation.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A unique poly-organic acid formulation that offers up to 150,000 miles of protection while being compatible with all cooling system metals and hose materials.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated coolant that greatly surpasses standards for metallic corrosion and erosion, ideal for long-life performance applications.
- AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Withstands the rigors of heavy towing and elevated temperatures while remaining fluid in sub-zero conditions.
- AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Designed to protect against wear and ensure smooth shifting in severe driving conditions.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Offers excellent ABS and traction-control responsiveness with stable viscosity over a wide temperature range.
- AMSOIL Gasoline Stabilizer – Helps keep fuel fresh for up to 12 months, protecting against varnish and gum buildup during storage.
- AMSOIL P.i. Performance Improver Gasoline Additive – Restores up to 14% horsepower and cleans GDI fuel injectors to 100% flow rate after just one tank of fuel.
Understanding the specific lubrication requirements for your vehicle begins with the heart of the machine: the engine. The 2021 GLC63 AMG is powered by the M177 4.0L V8 biturbo engine. This is a high-output powerplant that generates immense heat and torque. During operation, the engine oil must maintain a stable film thickness to prevent metal-to-metal contact between the pistons, bearings, and turbocharger shafts.
Engine Oil and Filtration Essentials
AMSOIL recommends a full 9.5-quart capacity for a complete oil change, including the filter. It is vital to refill the engine with the correct viscosity to meet the manufacturer’s tolerances. For the 2021 GLC63 AMG, the recommended grades are SEO30 Viscosity in 0W-30, 0W-40 for all temperatures, and 5W-30, 5W-40 for temperatures above -25°C. When changing the oil, torque the drain plug to 22 ft/lbs for a metal plug or 3 ft/lbs for a plastic plug, and always replace the drain plug seal.
While the source data does not specify a unique oil filter part number for this vehicle, using a high-quality filtration system alongside synthetic oil is non-negotiable. Synthetic oil contains fewer impurities than conventional oil, but it needs to work in tandem with an efficient filter to keep the engine internals clean. The AMSOIL 5W-40 FS and 0W-40 FS motor oils are formulated to meet the strict requirements of European engines, ensuring that the turbochargers are cooled and lubricated properly even during aggressive driving.
Cooling is equally important for this engine. The vehicle has a coolant capacity of 4.9 quarts for the LTCC4 or 11.7 quarts for the HTCC. Using a high-quality antifreeze like AMSOIL Passenger Car & Light Truck Antifreeze & Coolant or the Propylene Glycol version ensures the engine does not overheat during track days or hot summer traffic. These coolants are phosphate, nitrate, and silicate-free, which prevents scaling and extends the life of the water pump and radiator.
Transmission and Differential Protection
The GLC63 AMG relies on a sophisticated automatic transmission that requires precise fluid characteristics. AMSOIL’s Signature Series and OE Fuel-Efficient Automatic Transmission Fluids are ideal choices. These fluids are designed to protect against wear and sludge formation, which can be a problem in stop-and-go traffic or when towing heavy loads.
For the drivetrain, specifically the transfer case and rear differential, specific capacities apply. The transfer case requires 1.5 pints, with a drain plug torque of 18 ft/lbs and a fill plug torque of 10 ft/lbs. The front differential holds 1.3 pints, while the rear differential requires 2.5 pints. Using the correct gear lube ensures that these components remain quiet and responsive, preventing premature wear on the gears and bearings.
Brake Fluid and Maintenance
Brake performance is critical in a high-speed vehicle like the GLC63 AMG. The system requires a DOT 4 plus fluid, such as the product previously specified by Mercedes-Benz (0009895605090109). AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid meets or exceeds these requirements. It provides stable viscosity across a wide temperature range, ensuring consistent pedal feel and responsive ABS activation.
For owners who may be adding fuel additives to their tanks, the AMSOIL P.i. Performance Improver is a highly effective choice. It cleans GDI fuel injectors, restoring them to 100% flow rate and helping to control pre-ignition knock. This is particularly beneficial for turbocharged direct-injection engines, which can suffer from carbon buildup over time.
About the 2021 Mercedes-Benz GLC63 AMG
The 2021 Mercedes-Benz GLC63 AMG is a high-performance luxury compact SUV that stands at the intersection of sporty utility and everyday practicality. Produced by Mercedes-AMG, the company’s high-performance subsidiary, this model is powered by the M177 4.0-liter V8 biturbo engine. This powerplant is renowned for its massive power output, delivering acceleration that rivals dedicated sports cars while offering the utility of a crossover SUV.
The vehicle is based on the X253 platform, a generation of the GLC class that was designed to compete with other high-end compact SUVs like the BMW X5M and Audi Q7. What sets the GLC63 AMG apart is its aggressive tuning, featuring an 8-speed AMG SPEEDSHIFT TCT transmission and an intelligent all-wheel-drive system that can be configured for various driving modes. Owners appreciate the blend of daily drivability with track-capable performance. The car is known for its sharp handling, luxurious interior appointments, and a commanding road presence.
However, with great power comes the need for great maintenance. The GLC63 AMG is not immune to issues that can arise from high-stress driving conditions. One common problem in high-mileage AMG models is turbocharger shaft wear, often caused by thermal breakdown of standard oils. Using a robust synthetic oil like AMSOIL FS helps mitigate this by providing a durable film that resists shearing under high RPMs and heat.
Another known issue involves carbon buildup on the intake valves, particularly in Direct Injection (GDI) engines. As the vehicle ages, fuel carbon can accumulate, leading to rough idling or a loss of power. The AMSOIL P.i. additive is an excellent preventative measure, as it cleans injectors and helps maintain combustion efficiency. Additionally, transmission wear can become apparent if the fluid is not changed frequently enough. The high-torque nature of the V8 engine places significant stress on the transmission clutch packs, making a high-quality synthetic transmission fluid essential for longevity.
Finally, brake system performance can degrade if the fluid absorbs moisture over time. The GLC63 AMG’s braking system is a critical safety feature, and regular flushing with a high-boiling-point synthetic brake fluid ensures that the system remains responsive during hard stops, preventing brake fade.
In summary, maintaining the 2021 GLC63 AMG with premium synthetic lubricants is an investment in the vehicle’s future. By selecting the right oils, coolants, and additives, owners can ensure that this powerful SUV continues to deliver its legendary performance for miles to come.