The 2008 Jeep Grand Cherokee equipped with the 5.7L HEMI V8 is a capable vehicle, but it demands specific attention to maintenance to ensure longevity and peak performance. This engine, known for its Multiple Displacement System (MDS), requires strict adherence to viscosity standards to protect its internal components from wear. Using the wrong fluid can lead to sludge buildup, reduced fuel economy, and accelerated engine degradation. Proper lubrication is not merely a recommendation; it is a critical requirement for maintaining the structural integrity of the powertrain and keeping this iconic SUV running smoothly for years.
Recommended AMSOIL Products
- AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil – Provides the highest level of engine protection with 75% more resistance against horsepower loss and wear compared to conventional oils.
- AMSOIL Extended-Life 5W-20 100% Synthetic Motor Oil – Offers extended service intervals up to 20,000 miles with superior cleaning power to keep the engine running smoother for longer.
- AMSOIL OE 5W-20 100% Synthetic Motor Oil – A cost-effective 100% synthetic option that fights sludge and deposits while delivering protection comparable to top-tier manufacturers.
- AMSOIL 5W-20 100% Synthetic High-Mileage Motor Oil – Formulated specifically for vehicles over 75,000 miles with a boosted detergent package to clean and reduce sludge by 67%.
- AMSOIL Oil Filter – Delivers 99% filtration efficiency at 20 microns with lower restriction to ensure critical engine parts remain lubricated and protected.
- WIX Oil Filter – Features premium media that offers significant improvements over original equipment manufacturer branded filters for enhanced contamination control.
- WIX Air Filter – Utilizes premium filter media to protect the engine from harmful debris and improve airflow efficiency.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – An ethylene glycol 50/50 pre-mix designed to protect all cooling system metals and provide 150,000 miles of corrosion protection.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated option that greatly surpasses standards for metallic corrosion and erosion, offering extended service life.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Withstands heavy towing, elevated temperatures, and remains fluid in sub-zero conditions for superior transmission life.
- AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Promotes smooth, shudder-free shifts while guarding against leaks and harmful sludge buildup.
- WIX Transmission Filter – A deep pan filter designed for the 545RFE transmission to remove contaminants and protect the valve body and pump.
- AMSOIL 5W-30 100% Synthetic Tractor Hydraulic/Transmission Oil – An excellent friction-modified formulation for transfer cases like the NV245 that reduces chatter and ensures smooth operation.
- AMSOIL SEVERE GEAR® 75W-140 100% Synthetic Gear Lube – Offers advanced wear protection and controls thermal runaway in differentials, including limited-slip applications.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Provides a stable viscosity over a wide temperature range for excellent ABS and traction-control responsiveness.
Engine Oil Specifications and Selection
The 5.7L V8 engine in your 2008 Grand Cherokee is a robust powerplant, but it relies heavily on the correct viscosity to function as designed. For vehicles equipped with the Multiple Displacement System (MDS), the use of SAE 5W-20 oil is mandatory. This specific grade ensures the variable valve timing and cylinder deactivation systems operate correctly, preventing potential wear on the camshafts and lifters. The oil capacity for this engine, including a filter change, is 7 quarts. It is crucial to refill with the specified amount and then verify the level using the dipstick after the engine has been run and allowed to settle.
When selecting an oil, the AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil stands out as the premier choice for maximum protection. This premium synthetic offers up to 25,000 miles of guaranteed protection and is formulated to minimize horsepower loss due to friction. If your vehicle has higher mileage, the AMSOIL 5W-20 100% Synthetic High-Mileage Motor Oil is specifically designed to address wear patterns in engines over 75,000 miles. Its unique chemistry includes enhanced anti-wear additives and a boosted detergent package that reduces sludge by 67%, helping to restore performance and extend engine life.
Filter selection is equally critical. The AMSOIL Oil Filter provides a larger capacity for small, wear-causing contaminants compared to many competitors, helping to reduce engine wear over the long term. For those preferring a well-known aftermarket brand, the WIX Oil Filter offers premium media that improves upon the filtration performance of the original equipment manufacturer filters, ensuring clean oil circulates through the sensitive MDS components.
Transmission and Drivetrain Fluids
The automatic transmission in the 5.7L Grand Cherokee is a complex hydraulic system that requires fluid capable of withstanding extreme thermal loads and heavy towing. Whether you have the W5J400 or the 545RFE transmission, the fluid must maintain its viscosity and friction characteristics under stress. The total fill capacity varies by specific transmission model, ranging from 8.1 quarts for the W5J400 to 14.1 quarts for the 545RFE depending on the drive configuration.
For these systems, AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid is an excellent choice. It is engineered to remain fluid in sub-zero temperatures while providing reserve protection during heavy abuse. It helps maintain smooth shifts and guards against shudder. The AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid offers a robust alternative that resists sludge and protects against leaks, ensuring long-term reliability of the transmission bands and clutches.
Maintenance of the transfer case and differentials is often overlooked but vital for off-road enthusiasts. The NV140 transfer case requires a specific fluid type, and for the NV245, AMSOIL 5W-30 100% Synthetic Tractor Hydraulic/Transmission Oil is a highly effective solution. It reduces chatter and provides smooth operation for the transfer case mechanisms. For the front and rear differentials, which utilize limited-slip axles in many configurations, AMSOIL SEVERE GEAR® 75W-140 100% Synthetic Gear Lube is the recommended lubricant. It contains friction modifiers essential for limited-slip applications and helps control thermal runaway, which can degrade standard gear oils under heavy load.
Cooling, Braking, and Air Filtration
Proper thermal management is essential for the longevity of the 5.7L HEMI. The cooling system capacity is 14.5 quarts. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a 50/50 pre-mix that offers protection for 150,000 miles or five years. It is phosphate- and silicate-free, making it compatible with all cooling system metals and hoses. For those who prefer mixing their own, the AMSOIL Propylene Glycol Antifreeze and Engine Coolant provides exceptional corrosion protection and extends service intervals significantly.
Braking performance must remain consistent in all weather conditions. The AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid ensures excellent response for ABS and traction control systems. It maintains a stable viscosity across a wide temperature range, preventing the fluid from boiling under hard braking or thickening in freezing conditions.
Finally, ensuring the engine breathes properly is vital for efficiency. The WIX Air Filter uses premium media to trap dust and debris, preventing abrasive particles from entering the engine cylinders. This simple step significantly impacts fuel economy and engine wear over time.
About the Vehicle
The 2008 Jeep Grand Cherokee represents a significant era for the model line, characterized by the introduction of the new generation that debuted in 2005 and carried its refined features into the late 2000s. This vehicle sits firmly in the mid-size luxury SUV market, competing with vehicles like the Ford Explorer and the Chevrolet Tahoe. It is renowned for its rugged capability, offering four-wheel-drive systems that can handle serious off-road terrain while providing a comfortable ride quality on the highway.
The 5.7L HEMI V8 engine is the heart of the 2008 Grand Cherokee, delivering substantial power and torque. This engine is famous for its pushrod design and hemispherical combustion chambers, which contribute to its efficient breathing and robust power output. Owners often appreciate the vehicle’s versatility; it serves as a capable family hauler, a heavy-duty work vehicle, and an off-road adventurer all in one package. The interior space is generous, accommodating passengers and cargo with ease, while the available premium trims offer a level of luxury and technology that was ahead of its time.
For many drivers, the Grand Cherokee is the quintessential American SUV, blending utility with performance. The 2008 model year is particularly valued for its balance of traditional Jeep off-road prowess and modern on-road refinement. Owners tend to favor the 5.7L variant for its strong pulling power, which makes towing boats, campers, or trailers a viable option. This reputation for durability and capability has kept the model line popular for decades, making proper maintenance with high-quality synthetic fluids a smart investment for any owner looking to maximize their vehicle’s lifespan.