Maintaining the 2004 Infiniti I35 with the 3.5-liter VQ35DE engine requires more than just following the manual; it demands premium lubricants designed to meet the rigorous standards of Nissan’s powerplant. This engine, celebrated for its smooth power delivery and high-revving nature, relies heavily on the quality of its fluids to maintain longevity and performance. AMSOIL synthetic lubricants provide a superior alternative to conventional oils, offering enhanced protection against wear, sludge, and extreme temperatures. By choosing the right fluids, owners can ensure their vehicle remains responsive and reliable, whether it is being driven on long highway commutes or in stop-and-go city traffic.
Recommended AMSOIL Products
- AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil – The premier choice for maximum engine protection and extended drain intervals of up to 25,000 miles.
- AMSOIL Extended-Life 5W-30 100% Synthetic Motor Oil – An excellent option providing up to 20,000 miles of protection with superior cleaning power.
- AMSOIL OE 5W-30 100% Synthetic Motor Oil – A budget-friendly synthetic that outperforms conventional oils and meets OEM requirements.
- AMSOIL 5W-30 100% Synthetic High-Mileage Motor Oil – Specifically formulated for vehicles with over 75,000 miles to reduce leaks and consumption.
- AMSOIL Oil Filter – Designed with advanced filtration to trap 99% of contaminants at 20 microns, ensuring clean oil circulation.
- WIX Oil Filter – A high-quality alternative premium filter with improved media efficiency.
- WIX Air Filter – Enhances engine performance by effectively filtering incoming air to protect internal components.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A pre-mixed 50/50 formula offering 150,000-mile protection without the need for mixing.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated, non-ethylene glycol option for those seeking a safer, highly effective coolant solution.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Provides exceptional shear stability and thermal resistance for the I35’s automatic transmission.
- AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Promotes smooth shifts and guards against wear in automatic transmissions.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Features a high boiling point for stable braking performance under heavy load and in hot conditions.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – Formulated to keep seals soft, reduce friction, and prevent leaks while ensuring quiet operation.
Engine Oil Specifications and Selection
The heart of the 2004 Infiniti I35 is the VQ35DE 3.5-liter V6 engine. This powerplant is renowned for its durability and smooth operation, but it thrives best with high-quality lubrication. For this specific engine, AMSOIL recommends a 5W-30 viscosity grade. This grade is suitable for all temperature ranges, ensuring reliable starts in cold weather and stable oil film strength during high-temperature operation. The total oil capacity for the I35 is 4.2 quarts when changing the oil filter as well. After refilling, it is crucial to check the oil level with the dipstick to ensure it is within the safe operating range.
Selecting the correct oil allows you to tailor protection to the vehicle’s age and mileage. For newer or well-maintained engines, the AMSOIL Signature Series 5W-30 offers the highest level of protection. It provides 75% more protection against horsepower loss and wear compared to conventional oils. With a guaranteed 25,000-mile or one-year service interval, it is ideal for drivers who want maximum performance and the longest possible time between oil changes. The advanced additive package resists oxidation and helps maintain engine cleanliness.
If you are looking for a balance between performance and cost, the AMSOIL Extended-Life 5W-30 is a robust choice. It delivers up to 20,000 miles of protection and features 37% more cleaning power than the OE synthetic line. This helps prevent the buildup of sludge and deposits that can choke the engine over time. For those who prefer a product that closely mimics original equipment manufacturer (OEM) specifications, the AMSOIL OE 5W-30 is an excellent option. It fights sludge with a 100% synthetic formulation and has been proven to prevent Low-Speed Pre-Ignition (LSPI) events, ensuring the engine runs smoothly under various loads.
For the I35 with higher mileage, typically over 75,000 miles, the AMSOIL 5W-30 100% Synthetic High-Mileage Motor Oil is specifically engineered to address common aging engine issues. It contains a unique chemistry that includes boosted detergents and dispersants to clean out existing deposits. Furthermore, it features enhanced anti-wear additives that can help reduce oil consumption and minimize sludge formation by up to 67%. This formula helps seals remain pliable, reducing the likelihood of oil leaks, and guarantees protection for up to 12,000 miles or one year.
Transmission and Differential Fluids
The automatic transmission in the 2004 Infiniti I35 is the RE4F04B model. Proper maintenance of this transmission is critical for shifting performance and longevity. The total fill capacity for the automatic transmission is approximately 9 quarts. Using a synthetic transmission fluid can significantly improve the longevity of the transmission by reducing heat and preventing sludge buildup, which is a common issue in high-mileage automatic transmissions.
For maximum performance, the AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid is the top recommendation. This fluid is designed to withstand the rigors of heavy towing, elevated temperatures, and challenging terrain. It maintains fluidity even in sub-zero temperatures and provides a reserve of protection during severe use. Its formulation is compatible with a wide range of automatic transmissions and helps prevent shudder, ensuring smooth and precise gear changes.
The AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid offers a slightly different approach, focusing on smooth, shudder-free shifts while guarding against leaks. It provides excellent cold-weather performance and resists the formation of harmful sludge. This fluid is an ideal choice for drivers who want reliable, factory-like shifting characteristics with the added benefits of synthetic durability. Both of these transmission fluids offer extended service intervals, allowing you to save time and money on maintenance over the life of the vehicle.
Cooling, Braking, and Steering Systems
The cooling system of the I35 requires a high-quality antifreeze to protect against overheating and freezing. The engine’s total coolant capacity is 8.1 quarts. The AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is a phosphate-, nitrate-, and silicate-free formula that is compatible with all other coolant colors. It offers protection for up to 150,000 miles or five years, ensuring that the cooling system remains free from corrosion and deposits. For those who prefer a concentrated formula, the AMSOIL Propylene Glycol Antifreeze and Engine Coolant is a great alternative. It is safer than traditional ethylene glycol coolants and provides excellent protection against metallic corrosion and erosion.
Braking performance is paramount for safety. The I35 requires a DOT 3 hydraulic brake fluid. The AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid delivers excellent responsiveness for both ABS and traction control systems. Its stable viscosity across a wide temperature range ensures that the brake pedal remains firm and responsive, even during repeated hard stops. It does not absorb moisture as quickly as conventional fluids, which helps prevent brake fade and corrosion within the braking system.
The power steering system also benefits from synthetic lubrication. The recommended fluid for the I35 is compatible with Nissan ATF or equivalent fluids. The AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid reduces friction and helps seals remain soft to prevent leaks. It resists heat for a long fluid life and offers strong anti-wear protection. Formulated for quiet operation, this fluid ensures that the steering wheel turns smoothly without whining or grinding noises.
Filters and Air Intake
A high-quality AMSOIL Oil Filter is essential to ensure that the oil circulating through the engine is clean. This filter provides a filtration efficiency of 99 percent at 20 microns. This allows for lower restriction, keeping engine parts properly lubricated, and offers greater capacity for small, wear-causing contaminants than competing filters. This extended service life aligns with the extended drain intervals of AMSOIL synthetic oils.
For the air intake system, the WIX Air Filter is an excellent choice to ensure the engine receives clean air. A clean air filter improves airflow, which can enhance fuel economy and engine performance. By keeping dust and debris out of the engine, you help maintain the VQ35DE’s efficiency and reduce internal wear over time.
Seasonal Storage and Fuel System Care
If the Infiniti I35 is to be stored for an extended period, such as during winter months in colder climates, proper preservation is necessary. The AMSOIL Gasoline Stabilizer helps keep fuel fresh for up to 12 months, protecting against varnish and gum buildup. It fights ethanol corrosion, making it ideal for seasonal storage of vehicles and equipment.
For ongoing fuel system maintenance, the AMSOIL P.i. Performance Improver Gasoline Additive is highly recommended. This additive helps restore horsepower lost due to carbon deposits and restores GDI fuel injectors to 100% flow rate after just one tank of fuel. It improves fuel economy and helps control pre-ignition knock. For engines that have been sitting, the AMSOIL Engine Fogging Oil can be used to coat internal components, providing a rust-preventive barrier during long periods of inactivity.
About the Vehicle: The 2004 Infiniti I35
The 2004 Infiniti I35 represents a peak era for Infiniti’s sedan lineup, combining the brand’s reputation for luxury with a sporty driving character. Built on the Nissan F platform, the I35 is a mid-size luxury sedan that shares much of its architecture with the Nissan Maxima, offering a unique blend of comfort and performance. The model year 2004 features the 3.5-liter VQ35DE engine, a powerplant that is widely regarded by automotive enthusiasts as one of Nissan’s finest naturally aspirated V6 engines.
This engine is celebrated for its smooth power delivery, high-revving nature, and reliability. It produces sufficient horsepower to provide confident acceleration, making the I35 a favorite among drivers who enjoy spirited driving without the need for a turbocharger. The interior typically features high-quality materials, offering a quiet and refined cabin that belies the sporty engine beneath the hood. As a sedan, the I35 was designed for comfortable daily commuting while retaining enough agility to enjoy winding back roads.
Owners of the 2004 Infiniti I35 often praise the vehicle for its durability and the responsive steering, which gives the car a connection to the road that is rare in luxury sedans of its era. The VQ35DE engine is known for its longevity, often running well beyond 200,000 miles with proper maintenance. However, like any high-performance engine, it benefits immensely from the use of high-quality lubricants and fluids. By adhering to the recommended fluid specifications and using premium AMSOIL products, owners can continue to enjoy the smooth, reliable, and powerful performance that the I35 has been known for since its introduction.
Whether you are maintaining a daily driver or preserving a classic example of Japanese luxury engineering, the 2004 Infiniti I35 rewards owners who prioritize top-tier maintenance. The VQ35DE engine thrives on the stability and protection provided by synthetic lubricants, ensuring that the vehicle continues to perform as intended for years to come. With the correct fluids, filters, and additives, this sedan remains a compelling choice for those who appreciate a blend of luxury, reliability, and driving dynamics.