Maintaining the 2007 Ford Explorer with the 4.0L SOHC V6 engine requires strict adherence to the correct fluid specifications to ensure longevity and reliability. This engine, known for its durable overhead cam design, benefits significantly from high-quality synthetic lubricants that resist the breakdown common in higher-mileage applications. Proper fluid selection prevents wear, reduces operating temperatures, and helps manage the specific tolerances of the Power Stroke-derived 4.0L block. By utilizing the recommended products below, owners can extend service intervals, improve fuel economy, and protect critical engine components from the stress of daily driving, towing, or off-road use.
Recommended AMSOIL Products
- AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil – The top-tier choice offering unsurpassed engine protection for up to 25,000 miles, providing 75% more protection against horsepower loss and wear.
- AMSOIL Extended-Life 5W-30 100% Synthetic Motor Oil – Engineered for extended performance with 37% more cleaning power to keep the engine running smoother for up to 20,000 miles.
- AMSOIL Oil Filter – Features 99% filtration efficiency at 20 microns to trap contaminants and allows lower restriction for better lubrication of critical engine parts.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A long-lasting 50/50 pre-mix formulation that protects against corrosion and rust for up to 150,000 miles or 5 years.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Withstands heavy towing and elevated temperatures while remaining fluid in sub-zero conditions for smooth shifting.
- AMSOIL SEVERE GEAR® 75W-140 100% Synthetic Gear Lube – Specifically recommended for the rear conventional and limited-slip differentials to control thermal runaway and extend equipment life.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Provides excellent ABS responsiveness and maintains stable viscosity over a wide temperature range for safer stopping power.
The 4.0L SOHC engine in the 2007 Ford Explorer is a workhorse that demands specific maintenance to avoid common pitfalls associated with older high-mileage V6 powerplants. This engine was originally designed to offer a balance of power and fuel efficiency for a full-size SUV, but over time, oil degradation can lead to sludge buildup and excessive wear on the timing chain guides and bearings. Switching to a premium synthetic motor oil like the Signature Series or Extended-Life variants creates a superior film strength that shields these components from the harsh thermal and mechanical stresses of driving. The oil change capacity for this engine is 5.0 quarts when including a filter change, a detail that is critical when performing maintenance to ensure the crankcase is properly filled without overfilling.
Engine Oil and Filtration
Using the correct oil viscosity is paramount for the 4.0L SOHC engine. The recommended viscosity is 5W-30 for all temperature conditions, ensuring proper flow during cold starts while maintaining film strength at operating temperatures. AMSOIL Signature Series 5W-30 offers the highest level of protection, featuring a patented base stock formulation that resists shear and evaporation better than conventional oils. For owners with over 75,000 miles on their odometer, the 5W-30 High-Mileage Motor Oil is an excellent option, as it includes unique additives that help reduce oil consumption and clean existing sludge deposits that may have accumulated in the valve train.
Protection does not stop with the oil itself; the filtration system is equally vital. The AMSOIL Oil Filter is designed to trap 99% of contaminants at 20 microns, which is finer than many OEM filters. This high-efficiency filtration keeps the oil cleaner for longer, reducing wear on the camshaft, lifters, and main bearings. The filter also features a higher capacity for small contaminants compared to competing brands, allowing for the extended service intervals that synthetic oils are known for. When combined with the AMSOIL Extended-Life 5W-30, owners can safely drive up to 20,000 miles or one year between changes, whereas the Signature Series can extend that interval to 25,000 miles.
Transmission and Differential Care
The 2007 Ford Explorer comes equipped with automatic transmissions, most commonly the 5R55S for the five-speed or the 6R60 for the six-speed variants. These transmissions rely heavily on fluid integrity to manage shift quality and prevent slippage. AMSOIL Signature Series Multi-Vehicle Automatic Transmission Fluid is a top recommendation because it remains fluid even in sub-zero temperatures while withstanding the heat generated by heavy towing and challenging terrain. This fluid provides reserve protection during heavy use, helping to prevent the shudder and harsh shifts often experienced in older Ford transmissions as they age.
For the drivetrain, the front differential requires an 80W-90 AMSOIL SEVERE GEAR® 80W-90 100% Synthetic Gear Lube, while the rear differential generally calls for a 75W-140 synthetic gear lube. The AMSOIL SEVERE GEAR 80W-90 is ideal for the front, containing friction modifiers specifically for limited-slip applications to prevent chattering. For the rear axle, the 75W-140 variant is essential, especially for models with a Traction-Lok limited-slip differential. This synthetic gear lube offers advanced protection against wear and controls thermal runaway, which is a common failure mode in these axles. It also helps reduce operating temperatures, extending the life of the seals and gears.
Coolant, Brake Fluid, and Maintenance Tips
Cooling system health is often overlooked but is critical for the longevity of the 4.0L engine. The system capacity varies depending on whether the vehicle has an auxiliary heater, ranging from 12.2 to 13.9 quarts. AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a phosphate, nitrate, and nitrite-free formula that is compatible with all engine metals and rubber hoses. It provides protection up to 150,000 miles or five years, significantly reducing the risk of corrosion and overheating. For those who prefer a concentrated formula, the Propylene Glycol Antifreeze offers similar protection and allows for custom mixing ratios.
Brake fluid maintenance is another area where synthetic formulations shine. The AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid offers a stable viscosity over a wide temperature range, ensuring consistent pedal feel in both hot and cold weather. It also provides excellent responsiveness for ABS and traction control systems. When performing these fluid changes, owners should ensure they have the correct capacities on hand, such as the 12.4 quarts required for a total fill of the 5-speed 5R55S transmission or the 11.2 quarts for the 6-speed 6R60. Adhering to these specifications ensures the vehicle performs as intended, regardless of the load or driving conditions.
About the Vehicle
The 2007 Ford Explorer stands as a pivotal moment in the history of American mid-size SUVs, representing the final iteration of the body-on-frame platform that had been the industry standard for decades. This generation, built on the Ford U platform shared with the F-150, was renowned for its ruggedness and off-road capability. While the industry was rapidly shifting toward unibody crossovers, the 2007 Explorer retained a loyal following who appreciated its truck-like durability and towing prowess. It was a vehicle designed to handle heavy loads, navigate rough terrain, and provide ample passenger space, making it a favorite for families and outdoor enthusiasts alike.
Under the hood, the 4.0L SOHC V6 engine was the heart of many Explorer models during this period. Known as the “Twin Cam,” this engine was derived from the modular engine family used in Ford trucks and the Lincoln Town Car. It produced a respectable amount of torque, which was crucial for a vehicle of this size. The overhead cam design offered improved efficiency and power delivery compared to its pushrod predecessors, though it required diligent maintenance to manage the tension on the timing chain and guides, which are wear points on this specific engine. Despite these mechanical nuances, the 2007 Explorer is remembered for its spacious interior, versatile cargo area, and the confidence drivers felt behind the wheel when tackling challenging roads.
However, like any vehicle of this age, the 2007 Ford Explorer comes with a set of known issues that owners should be aware of. One of the most prevalent problems involves the timing chain tensioners and guides. As the engine accumulates miles, the plastic guides can wear out, and the tensioners can fail, leading to a noisy rattling sound from the front of the engine, particularly during cold starts. This issue can be exacerbated by using lower-quality oils that do not maintain sufficient viscosity to keep the hydraulic tensioners properly pressurized. Switching to a high-quality synthetic motor oil can help lubricate these components and reduce the likelihood of premature wear, while also making the engine run quieter.
Another common concern is related to the cooling system. The plastic components within the cooling system, such as the thermostat housing and radiator end tanks, can become brittle over time due to heat cycles and exposure to the elements. This brittleness can lead to leaks that are often mistaken for oil leaks, causing confusion during troubleshooting. Using a high-performance antifreeze that resists corrosion and maintains proper chemical balance can help mitigate internal rust and scaling that contributes to the degradation of these plastic parts. Furthermore, the automatic transmission in these vehicles is known to suffer from shudder or harsh shifting as the fluid degrades. Regular fluid exchanges with a synthetic transmission fluid formulated for high-temperature performance can significantly smooth out these shifts and extend the life of the transmission.
A final area of focus for owners is the oil consumption and valve cover gasket leaks. The 4.0L engine can be prone to consuming oil or leaking from the valve covers as the seals age. The AMSOIL High-Mileage Motor Oil is specifically designed to address these concerns. Its enhanced seal conditioning agents help swell and rejuvenate aging rubber seals, potentially reducing or eliminating oil leaks. Additionally, the boosted detergent package in the high-mileage formulation helps clean out the deposits that can contribute to oil consumption, ensuring that the engine runs cleaner and more efficiently for years to come. By addressing these specific vulnerabilities with the right fluids, owners can keep their 2007 Ford Explorer in peak condition, ready for whatever the road or trail has to offer.