The 2008 Jeep Grand Cherokee equipped with the massive 6.1-liter V8 Hemi engine is a powerhouse on and off the road, but that power comes with demanding maintenance requirements. Keeping this high-performance SUV running smoothly requires more than just a routine oil change; it demands precise fluid management throughout the entire vehicle. Using the correct lubricants ensures that the engine’s delicate internal components are protected from wear, the transmission shifts smoothly under heavy loads, and the cooling system effectively manages the heat generated by this high-output engine. Neglecting fluid quality can lead to premature wear, reduced fuel economy, and costly repairs, making the choice of lubricants a critical decision for any owner.
Recommended AMSOIL Products
- AMSOIL Signature Series 0W-40 100% Synthetic Motor Oil – The premier choice for this Hemi engine, offering superior protection against high temperatures and horsepower loss, with service intervals up to 25,000 miles.
- AMSOIL Oil Filter (EAO11) – Features 99% efficiency at 20 microns and lower restriction to ensure optimal lubrication and engine longevity.
- WIX Oil Filter – A premium aftermarket alternative with advanced media that outperforms OEM-branded filters.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A unique OAT formulation that exceeds OEM requirements and protects all cooling system metals for up to 150,000 miles.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Designed to withstand heavy towing, elevated temperatures, and challenging terrain while maintaining fluidity in sub-zero conditions.
- AMSOIL SEVERE GEAR 75W-140 100% Synthetic Gear Lube – Provides advanced protection against wear and thermal runaway for both front and rear differentials, including limited-slip applications.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent ABS and traction-control responsiveness with a stable viscosity across a wide temperature range.
Understanding the specific needs of the 6.1L engine is the first step in maintaining this vehicle. The engine requires a robust oil capacity of 7.0 quarts when including the filter replacement. For optimal protection, the recommended viscosity is 0W-40 for all temperature ranges. This specific grade allows for easier cold starts and maintains a stable film strength during the high-heat operation characteristic of the Hemi V8. The oil drain plug should be torqued to 20 ft/lbs, and it is crucial to check the oil level after the refill to ensure the correct amount is circulating through the engine galleries.
Engine Protection and Filtration
While the 6.1L engine is legendary for its torque and power, it demands a filter that can handle the increased volume of oil and the potential for higher contamination levels found in performance applications. The standard filter options available include the AMSOIL Oil Filter (EAO11) and the EAO42, both of which offer extended service life and high filtering efficiency. These filters are engineered to allow lower restriction, which keeps engine parts better lubricated, and provide a greater capacity for capturing small, wear-causing contaminants compared to many competing brands.
For owners seeking a premium aftermarket alternative, the WIX Oil Filter (57899) is also a viable option. It features premium media that offers improvements over original equipment manufacturer-branded filters, ensuring that the engine receives clean oil to operate efficiently. Selecting the right filter is not just about capturing debris; it is about maintaining oil pressure and ensuring that the oil change intervals can be extended safely, reducing the frequency of maintenance tasks without compromising engine health.
Transmission and Drivetrain Lubrication
The 2008 Grand Cherokee’s automatic transmission is a critical component that endures significant stress, especially when the vehicle is used for towing or hauling. The automatic transmission fluid (ATF) requirements vary slightly depending on the specific transmission model, such as the W5A580. For a total fill, the system may require up to 8.1 quarts, while an initial fill is approximately 5.3 quarts. The 6.1L model is particularly suited for the AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid or the AMSOIL Signature Series Multi-Vehicle fluid, which are formulated to remain fluid in sub-zero temperatures while resisting degradation under heavy use.
The drivetrain, including the transfer case and differentials, also benefits from synthetic lubrication. The transfer case, specifically the NV140 and NV245 models, requires specific fill amounts; the NV140 takes 1.5 pints, while the NV245 requires 3.8 pints. For these components, AMSOIL offers a versatile solution using the Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid or the AMSOIL 5W-30 100% Synthetic Tractor Hydraulic/Transmission Oil, depending on the specific application and manufacturer recommendations.
The front and rear differentials, identified by codes C200F, C200FE, C213R, and C213RE, utilize 75W-140 gear lube. Whether the vehicle has a standard or limited-slip differential, the AMSOIL SEVERE GEAR 75W-140 100% Synthetic Gear Lube is the recommended choice. This synthetic gear lube contains friction modifiers specifically for limited-slip applications, which helps prevent the chatter and squeal often associated with these differentials. It also controls thermal runaway and helps reduce operating temperatures, extending the life of the seals and gears. For limited-slip differentials, it is important to note that adding 4 oz of Mopar limited-slip additive is required to meet factory specifications.
Cooling and Brake Systems
The cooling system in the 2008 Grand Cherokee holds a substantial volume of 14.5 quarts. Over time, standard coolants can break down, leading to corrosion and reduced heat transfer efficiency. Replacing the factory fluid with AMSOIL Propylene Glycol Antifreeze and Engine Coolant ensures protection for up to 150,000 miles or 5 years. This formulation is phosphate-, nitrate-, nitrite-, silicate-, borate-, and amine-free, making it safe for all cooling system metals, gaskets, and hoses. It is an ethylene glycol 50/50 pre-mix, meaning it is ready to use without the need for additional water, provided it is the pre-mixed version.
For the braking system, safety is paramount. The recommended fluid is a hydraulic brake fluid meeting the MS-4574 specification. AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid is designed to provide excellent responsiveness for both ABS and traction-control systems. Unlike conventional fluids, the synthetic version maintains a stable viscosity over a wide temperature range, ensuring consistent brake pedal feel in both freezing winter conditions and hot summer driving scenarios.
Additional Maintenance and Seasonal Care
Proper maintenance extends beyond just changing fluids; it involves protecting the vehicle during storage and ensuring the fuel system remains clean. For owners who may store the vehicle for extended periods, AMSOIL Gasoline Stabilizer helps keep fuel fresh for up to 12 months, preventing the varnish and gum buildup that can clog injectors. Additionally, AMSOIL Engine Fogging Oil can be used to protect internal engine components from rust during long periods of inactivity.
To maximize the efficiency of the engine, the AMSOIL P.i. Performance Improver is a powerful additive. It restores up to 14% of horsepower and cleans fuel injectors back to 100% flow rate after just one tank of treated fuel. This is particularly beneficial for direct injection engines, which are prone to carbon buildup. For general cleaning and protection, the AMSOIL P.C. Preferred Customer program offers reduced pricing on all these products, making regular maintenance more affordable. For owners seeking air filtration solutions, WIX Air Filters provide premium media that improves upon OEM options, and WIX Cabin Air Filters help maintain a clean interior environment.
About the Vehicle
The 2008 Jeep Grand Cherokee represents a peak era for the fourth-generation WK model, particularly when equipped with the 6.1-liter Hemi V8. This specific engine, part of the Chrysler 360 Hemi family, was the largest displacement V8 engine available in the Grand Cherokee lineup at the time. It produced approximately 425 horsepower and 420 lb-ft of torque, giving the mid-size SUV performance capabilities that rivaled smaller luxury vehicles. The 6.1L engine was a favorite among enthusiasts for its smooth power delivery, distinct exhaust note, and the sheer capability to move a heavy vehicle with ease.
On the platform front, the Grand Cherokee utilized a body-on-frame construction for earlier generations, but the 2008 model had transitioned to a unibody design with advanced suspension technology. This shift improved on-road handling and ride comfort while retaining significant off-road credentials. The vehicle was available with various drivetrain configurations, including the Quadra-Drive and Quadra-Trac four-wheel-drive systems, which utilized electronic controls to distribute power between the front and rear axles, and even between the wheels on the same axle, to maintain traction on difficult terrain. The interior was designed to blend utility with luxury, featuring high-quality materials and a robust suite of features for the era.
Owners of the 6.1L model often cite its unique position in the market: a vehicle that could tow a boat or a trailer to a camping spot and then serve as a comfortable daily driver. The engine was renowned for its longevity when properly maintained, and the transmission was designed to handle the high torque output. However, the performance nature of the vehicle meant that it required attentive care regarding fluid changes and filter replacements to sustain its performance characteristics over the long term. Whether used for weekend adventures or daily commuting, the Grand Cherokee 6.1L remains a respected and capable vehicle in the SUV segment.