Maintaining your 2008 Jeep Grand Cherokee with the 3.7L engine requires specific lubricants to ensure longevity and peak performance. Proper fluid selection is critical because the engine was designed with precise clearances and operating temperatures that demand consistent protection. Using the wrong viscosity or grade can lead to premature wear, reduced fuel economy, and costly repairs. Whether you are navigating daily commutes, tackling off-road trails, or towing heavy loads, your vehicle needs high-quality synthetic lubricants that can withstand extreme conditions. Products like AMSOIL 5W-30 Tractor Hydraulic/Transmission Oil and AMSOIL SEVERE GEAR Gear Lube provide the heavy-duty protection needed for these demanding applications.
Recommended AMSOIL Products
- AMSOIL Signature Series 5W-20 100% Synthetic Motor Oil – The top-tier choice offering up to 25,000 miles of protection and superior wear defense.
- AMSOIL Extended-Life 5W-20 100% Synthetic Motor Oil – Provides a balanced solution for extended service intervals up to 20,000 miles.
- AMSOIL OE 5W-20 100% Synthetic Motor Oil – An OEM-mileage synthetic oil that fights sludge and deposits effectively.
- AMSOIL 5W-20 100% Synthetic High-Mileage Motor Oil – Formulated specifically for engines with over 75,000 miles to reduce leaks and consumption.
- AMSOIL Oil Filter – Delivers 99% filtration efficiency and higher contaminant capacity than standard filters.
- WIX XP Oil Filter – Features premium media that outperforms original equipment manufacturer-branded filters.
- WIX Oil Filter – A reliable option offering premium media for improved protection.
- WIX Air Filter – Ensures clean airflow to the engine with premium filtration media.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A 50/50 pre-mix formulation that protects cooling system components for up to 150,000 miles.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated option for superior corrosion protection and extended service life.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Designed to withstand towing and extreme temperatures while maintaining fluidity in sub-zero conditions.
- AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Promotes smooth shifts and guards against sludge and leaks.
- AMSOIL 5W-30 100% Synthetic Tractor Hydraulic/Transmission Oil – An excellent choice for transfer cases requiring versatile fluid performance.
- AMSOIL SEVERE GEAR 75W-140 100% Synthetic Gear Lube – Advanced protection for front and rear differentials, controlling thermal runaway and protecting limited-slip units.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Offers excellent responsiveness for ABS systems and stable viscosity across wide temperature ranges.
Engine Oil and Filtration Specifications
The 3.7L V6 engine in the 2008 Grand Cherokee is a robust powerplant, but it demands precise lubrication to maintain its lifespan. The manufacturer specifies a 5W-20 viscosity grade for all temperatures. The oil capacity for this engine is 5.0 quarts when including the filter. It is crucial to adhere to this amount, as overfilling can cause foaming and pressure issues, while underfilling risks insufficient lubrication.
For those seeking the absolute best protection, AMSOIL Signature Series 5W-20 is the premier choice. This oil provides 75% more engine protection against horsepower loss and wear compared to industry standards. It guarantees protection for up to 25,000 miles or one year, whichever comes first. If you prefer a slightly shorter interval or a cost-effective high-performance option, the Extended-Life 5W-20 offers up to 20,000 miles of protection. It features enhanced cleaning power to keep the engine running smoother for longer.
For drivers prioritizing an OEM-like experience, the AMSOIL OE 5W-20 100% Synthetic Motor Oil is an excellent alternative. It fights sludge and deposits effectively while preventing Low-Speed Pre-Ignition (LSPI) events. If your vehicle has accumulated more than 75,000 miles, the High-Mileage 5W-20 is specifically designed to reduce leaks and consumption, featuring a boosted detergent package to keep internal components clean.
Filtration is just as vital as the oil itself. The recommended filter for this application is the AMSOIL Oil Filter, model EAO34-EA. This filter offers filtering efficiency of 99 percent at 20 microns, allowing for lower restriction and keeping engine parts properly lubricated. It has greater capacity for small, wear-causing contaminants than competing filters. For those who prefer aftermarket brands, the WIX XP Oil Filter and WIX Oil Filter are also recommended, both offering premium media that improves upon OEM-branded filters.
Changing the oil is a critical maintenance task. The drain plug torque should be set to 25 ft/lbs. Regular oil changes prevent the buildup of acidic byproducts and sludge that can damage the engine. By using a high-quality synthetic oil and an effective filter, you ensure that the 3.7L engine receives the cleanest possible lubricant, reducing friction and extending the life of critical components like pistons, rings, and bearings.
Transmission and Transfer Case Fluids
The automatic transmission in the 2008 Jeep Grand Cherokee, specifically the 545RFE and W5J400 models, requires a fluid that can handle the demands of four-wheel driving. These transmissions benefit greatly from a synthetic fluid that resists thermal breakdown and maintains viscosity in extreme temperatures. The capacity for a total fill varies by model, with some requiring up to 14.1 quarts for the 5-speed 545RFE 4WD, while the initial fill is around 5.3 to 6.6 quarts depending on the specific transmission code.
AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid is a standout choice. It remains fluid in sub-zero temperatures and withstands the rigors of heavy towing and challenging terrain. This fluid provides reserve protection during heavy use, ensuring smooth shifts and preventing shudder. For those seeking an alternative, the AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid offers excellent cold-weather performance and resistance to harmful sludge, promoting smooth, shudder-free shifts.
For vehicles equipped with a transfer case, lubrication choices depend on the model. The NV140 transfer case requires a small capacity of 1.5 pints, while the NV245 requires 3.8 pints. The NV140 can utilize the Signature Series or OE Multi-Vehicle ATF. However, the NV245 is best served by AMSOIL 5W-30 100% Synthetic Tractor Hydraulic/Transmission Oil. This fluid offers excellent hot- and cold-weather protection, reducing the need for seasonal changes and providing superior anti-wear additives for pumps and valves.
Differential Lubrication and Coolant
The front and rear differentials in the Grand Cherokee operate under high stress, especially when off-roading. The front differential (C200F or C200FE) requires 3.6 pints of lubricant. The rear differential (C213R or C213RE) requires 4.4 pints. For standard applications, AMSOIL SEVERE GEAR 75W-140 100% Synthetic Gear Lube is the ideal choice. This gear lube provides advanced protection against wear, controls thermal runaway, and helps reduce operating temperatures. It contains friction modifiers suitable for limited-slip applications.
If your vehicle has a limited-slip differential, you must add 4 oz of Mopar limited-slip additive (MS-10111) to the gear lube to ensure proper operation. The SEVERE GEAR product protects against rust and corrosion while extending the life of seals and gears, making it a superior choice for maintaining the drivetrain’s integrity over the long term.
Regarding coolant, the 2008 Grand Cherokee requires 10 quarts of antifreeze. AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a phosphate-, nitrate-, nitrite-, silicate-, borate-, and amine-free formulation. It is engineered to exceed original equipment manufacturer requirements and provides protection up to 150,000 miles or five years. For those who prefer a concentrated solution, the AMSOIL Propylene Glycol Antifreeze and Engine Coolant offers even longer protection intervals and greatly surpasses standards for metallic corrosion and erosion.
Brake Fluid and Additional Care
Safety is paramount, and the braking system relies on a high-quality fluid. The recommended fluid is AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid. This fluid provides excellent ABS and traction-control responsiveness while maintaining a stable viscosity over a wide temperature range. It ensures that braking performance remains consistent even under hard use or in extreme weather conditions.
For seasonal storage or to maintain fuel system health, AMSOIL Gasoline Stabilizer helps keep fuel fresh for up to 12 months, protecting against varnish and gum buildup. The AMSOIL P.i. Performance Improver Gasoline Additive can restore up to 14% horsepower and improve fuel economy. Additionally, AMSOIL Upper Cylinder Lubricant Corrosion Inhibitor lubricates the fuel system and upper cylinders, keeping the engine running smoothly.
About the 2008 Jeep Grand Cherokee
The 2008 Jeep Grand Cherokee stands as a testament to the brand’s legacy of building capable and versatile SUVs. Part of the WK generation, which was introduced in 2005, the 2008 model year continued to offer a blend of on-road comfort and off-road prowess that defined the vehicle’s reputation. Under the hood, the 3.7L PowerTech V6 engine was a standard offering, providing a balance of reliability and sufficient power for daily driving and light hauling. While not the most powerful engine in the lineup compared to the Hemi V8 options, the 3.7L was known for its durability and was a popular choice for owners who valued fuel efficiency and low maintenance costs.
Visually, the 2008 model featured the distinctive seven-slot grille and rugged stance that Jeep enthusiasts have come to expect. The Grand Cherokee offered a spacious interior, comfortable seating for five adults, and a cargo area that was practical for families or outdoor enthusiasts. The vehicle’s four-wheel-drive systems, available in both part-time and full-time configurations, made it a favorite for navigating snow-covered roads, dirt trails, and muddy terrain.
Owners often praise the Grand Cherokee for its solid build quality and ride quality, which offered a smoother experience compared to many of its competitors at the time. The suspension system provided a good compromise between comfort and handling, allowing the vehicle to absorb bumps without feeling wallowy. With proper maintenance, particularly regarding the fluids discussed in this guide, the 2008 Grand Cherokee remains a reliable and capable vehicle that can serve its owners well for many years to come.