The 2008 Mercedes-Benz G55 AMG is a high-performance machine built on the robust G-Class platform, designed to handle extreme demands while delivering the luxury and comfort expected of the Mercedes-Benz brand. With its naturally aspirated 5.5-liter V8 engine producing significant power, the vehicle requires lubrication solutions that can withstand high thermal loads, extreme pressures, and the specific material requirements of European engineering. Using the correct fluids is essential for maintaining engine longevity, preserving transmission performance, and ensuring safe braking capabilities in this demanding SUV.
Recommended AMSOIL Products
For the 2008 Mercedes-Benz G55 AMG, AMSOIL provides specialized synthetic lubricants designed to exceed OEM standards. The following products offer optimal protection for the engine, transmission, and other critical systems.
- 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 protect high-performance engines.
- AMSOIL 0W-40 FS 100% Synthetic European Motor Oil – An alternative European formula designed for extreme temperature performance and superior engine cleanliness, ideal for maintaining peak horsepower and efficiency.
- AMSOIL Oil Filter – Provides filtration efficiency of 99 percent at 20 microns to keep engine parts lubricated and reduce wear caused by small contaminants.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A unique poly-organic acid (OAT) formulation that protects cooling system metals, gaskets, and hoses for up to 150,000 miles or 5 years.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated option that can be mixed with water, offering protection up to 150,000 miles in passenger cars and light trucks while vastly surpassing corrosion standards.
- 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 – Protects against wear and is formulated to meet original equipment specifications for optimal transmission performance.
- 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.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – Reduces friction, helps seals remain soft to prevent leaks, and offers excellent high-temperature protection for quiet operation.
Engine Oil and Filter Specifications
Proper lubrication begins with the engine oil, which serves as the lifeblood of the 5.5-liter V8 engine in your G55 AMG. The engine oil capacity for this vehicle is 9.0 quarts, including the AMSOIL Oil Filter replacement. It is critical to select a viscosity that matches the operating conditions; AMSOIL recommends either 0W-30, 0W-40 for all temperatures, or 5W-30, 5W-40 for conditions above -25°C. For the ultimate in protection against European-specific wear patterns, the AMSOIL 5W-40 FS is a top choice, offering a European formula with a precise blend of synthetic base oils. Alternatively, for colder climates or extended cold starts, the AMSOIL 0W-40 FS provides superior cold-flow properties while maintaining high-temperature stability.
Filtering is just as important as the oil itself. The oil should be drained and the filter replaced every time, with the oil drain plug torqued to 22 ft-lbs. For filtration, the AMSOIL Oil Filter (EA15K39-EA) is an excellent option, boasting a capacity for small contaminants that reduces engine wear and offers extended service life. If you prefer an alternative, the WIX Oil Filter and MANN-FILTERS Oil Filter are also compatible and offer premium media improvements over standard OEM filters.
Transmission and Cooling Systems
The automatic transmission in the 2008 G55 AMG is a critical component that requires fluid specifically designed for the 722.6 series. For a total fill, the capacity is 9 quarts. Using a synthetic fluid ensures that the transmission remains fluid in sub-zero temperatures and provides reserve protection during heavy use. The AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid is designed to withstand elevated temperatures and heavy towing, making it ideal for the G-Wagen’s capabilities. For those seeking a fluid that meets OE specifications closely, the AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid offers excellent wear protection.
Coolant management is vital for the high-performance engine of the G55 AMG. The cooling system holds 13.4 quarts of fluid. AMSOIL offers two robust options. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a 50/50 pre-mixed ethylene glycol solution that protects all cooling system metals and is phosphate, nitrate, nitrite, silicate, borate, and amine-free. For those who prefer a concentrate that can be mixed with distilled water for maximum corrosion protection, the AMSOIL Propylene Glycol Antifreeze and Engine Coolant is a high-performance choice that lasts up to 150,000 miles or 5 years.
Brake, Power Steering, and Seasonal Care
Brake safety is paramount for a vehicle of this caliber. The G55 AMG requires brake fluid that meets DOT 4 plus or MB Sheet 331.0 specifications. The AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid provides excellent responsiveness for ABS and traction control systems, ensuring consistent pedal feel in all weather conditions.
The power steering system also benefits from synthetic technology. The AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid is formulated to keep seals soft to prevent leaks, reduce friction, and resist heat for long fluid life, ensuring quiet operation.
For vehicles that see seasonal storage, protection against fuel degradation and internal rust is essential. The AMSOIL Gasoline Stabilizer helps keep fuel fresh for up to 12 months, protecting against varnish, gum buildup, and ethanol corrosion. When preparing the engine for long periods of inactivity, the AMSOIL Engine Fogging Oil provides a highly effective rust preventive that coats internal engine components to prevent corrosion.
Additional Protection and Fuel System Maintenance
Maintaining peak performance involves more than just changing fluids; it also involves keeping the fuel system clean and protecting exterior surfaces. The AMSOIL P.i. Performance Improver Gasoline Additive is a powerful tool that can restore up to 14% of lost horsepower and clean GDI fuel injectors to 100% flow rate after one tank. This additive also helps control pre-ignition knock and improves fuel economy.
To further protect the engine during storage or in cold weather, the AMSOIL Upper Cylinder Lubricant Corrosion Inhibitor lubricates the fuel system and upper cylinders, compatible with capless fuel systems. For exterior maintenance, the AMSOIL Heavy-Duty Metal Protector offers long-lasting corrosion protection against salt and moisture, leaving a wax-like coating that shields steel, iron, and aluminum surfaces.
When cleaning is required, the AMSOIL Power Foam® Carburetor and Induction-System Cleaner removes deposits and restores startability. For general washing, the AMSOIL Miracle Wash Waterless Wash and Wax Spray provides a tough protective finish that repels dust and protects against UV rays. To tackle tough grime, the AMSOIL Heavy-Duty Degreaser quickly dissolves oil and tar. Finally, the AMSOIL Silicone Spray offers a dry lubricating film that locks out moisture without attracting dirt, protecting rubber surfaces.
About the Vehicle
The 2008 Mercedes-Benz G55 AMG represents the pinnacle of the G-Class lineage during that era, combining legendary off-road capability with the power of a high-performance AMG engine. Unlike the typical diesel engines found in G-Wagens of that period, the G55 AMG is powered by the naturally aspirated 5.5-liter M113 V8 engine. This engine was a flagship powerplant for Mercedes-AMG, delivering over 500 horsepower and significant torque, allowing the heavy, boxy SUV to accelerate with surprising speed. The vehicle’s design is rooted in the G-Class platform, originally developed for military and utility use, which translates to its enduring boxy silhouette and exceptional ground clearance. Owners appreciate this model for its unique character: it is one of the few vehicles that can traverse rugged terrain while offering the luxury and refinement expected of a Mercedes-Benz on the highway. The interior typically features premium leather, wood trim, and AMG-specific sport seats. Its robust construction and the engineering quality of the AMG division make it a highly sought-after model for enthusiasts who value both performance heritage and practical utility. The vehicle’s reputation is built on its ability to handle severe conditions without compromising the driving experience, making it a favorite among collectors and daily drivers alike.