Ensuring your 2007 Mercedes-Benz GL450 receives the correct lubricants is critical for maintaining the longevity of its 4.7-liter V8 engine and complex drivetrain. This luxury SUV, powered by the robust engine code 273.923, operates under significant thermal and mechanical stress, especially when towing or driving in extreme weather conditions. Using the right viscosity and formulation prevents premature wear, reduces friction, and helps maintain fuel efficiency over the vehicle’s service life.
Recommended AMSOIL Products
For the engine, the specific requirements of this German vehicle demand a European-formulated synthetic oil that provides superior thermal stability and wear protection. The following products are tailored for the 2007 GL450:
- AMSOIL 5W-40 FS 100% Synthetic European Motor Oil – Designed specifically for the precise demands of European gasoline, diesel, and hybrid engines, this oil offers a precise blend of synthetic base oils and premium additives to protect the 4.7L V8.
- AMSOIL 0W-40 FS 100% Synthetic European Motor Oil – An excellent alternative for extreme cold weather or high-mileage applications, providing superior flow characteristics while maintaining film strength under heavy loads.
- AMSOIL Oil Filter – Engineered with superior filtration efficiency, this filter captures small, wear-causing contaminants more effectively than competing brands, keeping engine parts lubricated and extending oil change intervals.
- WIX Oil Filter – Premium media offers improvements over original equipment manufacturer (OEM)-branded filters, providing reliable protection for the engine.
- MANN-FILTERS Oil Filter – Premium media offers improvements over original equipment manufacturer (OEM)-branded filters, providing reliable protection for the engine.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A phosphate-, nitrate-, nitrite-, silicate-, and borate-free formula that protects the 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 requiring mixing with distilled water, this formula offers protection up to 150,000 miles or 5 years.
- AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Withstands the rigors of heavy towing and elevated temperatures common in GL450 operation, remaining fluid in sub-zero temperatures to ensure smooth, shudder-free shifts.
- AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – A cost-effective option that still provides outstanding protection against wear and sludge, promoting smooth operation for the 7-speed 722.9 transmission.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent ABS and traction-control responsiveness with a stable viscosity over a wide temperature range, essential for the safety of this heavy SUV.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – Reduces friction and helps seals remain soft to prevent leaks, ensuring the power steering system operates quietly and efficiently throughout the vehicle’s life.
Proper lubrication extends far beyond just the engine. The 2007 GL450 relies on a sophisticated network of fluids to manage the transfer of power from the engine to the wheels. The automatic transmission, in particular, operates at high pressures and temperatures. Using a high-quality synthetic fluid like the AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid ensures that the torque converter and clutch packs remain protected against the shear forces generated during towing or spirited driving. Similarly, the transfer case, which allows for 4WD operation, requires fluid that can handle the sudden shifts in torque distribution. The recommended products listed above are formulated to meet or exceed the strict factory specifications required for these specific components.
When performing maintenance on this vehicle, capacity and specifications must be respected to avoid damage. The engine oil capacity for the 4.7L V8 is 9.0 quarts when the filter is included. After refilling, it is crucial to check the oil level to ensure proper lubrication. The torque specification for the oil drain plug is 25 ft/lbs. For the cooling system, the capacity is 10.6 quarts. The 7-speed automatic transmission (722.9) requires a total fill of 9.5 quarts, though specific variations in the 722.9 code (SL057 vs. SL058) may dictate fluid type slightly differently regarding reduced-friction codes, making the synthetic transmission fluids a versatile choice for both configurations.
Maintenance intervals can be extended significantly with AMSOIL synthetic products without compromising protection. While OEM recommendations may suggest frequent changes, high-performance synthetic motor oils maintain their viscosity and additive strength for longer periods. This is particularly beneficial for the GL450, where carbon buildup on fuel injectors and valve deposits can occur over time. Incorporating an additive like AMSOIL P.i. Performance Improver can help restore up to 14% horsepower and clean GDI fuel injectors to 100% flow rate, ensuring the engine breathes efficiently and runs smoothly.
About the Vehicle
The 2007 Mercedes-Benz GL450 represents a significant chapter in the brand’s history, serving as the luxury SUV flagship that bridged the gap between traditional rugged off-roaders and high-end road cruisers. As the successor to the ML Class, the GL450 introduced three rows of seating to the Mercedes SUV lineup, transforming it from a two-row mid-size luxury SUV into a seven-passenger vehicle capable of accommodating families without sacrificing the premium comfort and status associated with the three-pointed star.
Under the hood, the GL450 is powered by the robust M273 4.7-liter V8 engine. This naturally aspirated powerhouse produces substantial horsepower and torque, delivering a driving character that prioritizes smooth, linear acceleration over the high-revving sportiness of smaller engines. The engine is known for its refinement, with excellent NVH (Noise, Vibration, and Harshness) characteristics that make long-distance highway travel comfortable and quiet. The vehicle sits on a unibody construction with multi-link suspension, offering a ride quality that rivals luxury sedans while retaining the ability to handle light to moderate off-road terrain thanks to its optional 4MATIC all-wheel-drive system.
Owners of the GL450 typically value its versatility. It is a vehicle that can comfortably haul a full load of passengers and cargo, tow small trailers or boats, and still serve as the primary daily driver for a family. The interior is characterized by high-quality materials, including leather upholstery, wood trim, and advanced technology for its time, such as the COMAND infotainment system. The market position of the GL450 was strong during its production years, competing directly with vehicles like the Cadillac Escalade, Lexus LX, and Lincoln Navigator, but with a distinct emphasis on European engineering and driving dynamics.
However, with age comes the need for diligent maintenance. Several known issues have been associated with this generation of the GL450 that proper lubrication and fluid care can help mitigate. One common problem is oil consumption, which can lead to low oil levels and potential engine wear if not monitored and addressed. The use of high-quality synthetic oils with robust additive packages can help control oil consumption and maintain proper ring sealing. Another issue involves the cooling system; the 4.7L engine requires a AMSOIL Passenger Car & Light Truck Antifreeze & Coolant that can prevent corrosion and manage the high thermal loads generated by the V8. Using a high-performance antifreeze like the AMSOIL Passenger Car & Light Truck formula helps prevent scale and corrosion buildup in the radiator and engine block.
Transmission issues can also arise, particularly if the fluid degrades over time or is not replaced with the correct specification. The 7-speed automatic transmission is sensitive to fluid condition, and degraded fluid can lead to harsh shifting or shudder. Regular fluid exchanges with a synthetic transmission fluid designed for German vehicles can restore smooth operation and protect the transmission bands. Finally, the power steering system can suffer from seal leaks as the vehicle ages, leading to fluid loss and noise. Switching to a high-quality synthetic AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid helps keep seals pliable and resistant to leakage, ensuring the steering remains responsive and quiet for years to come.