Maintaining the 2018 Infiniti Q70L with its naturally aspirated 3.7-liter VQ37VHR 3 engine requires a disciplined approach to lubrication. This luxury sedan, powered by a 325-horsepower V6, was designed for a smooth, responsive driving experience that relies heavily on the quality of its internal fluids. Over time, standard mineral oils break down, leaving vulnerable components like the timing chain guides, valve train, and turbochargers (on other models in the lineup) susceptible to wear. AMSOIL synthetic lubricants are formulated to exceed original equipment manufacturer specifications, ensuring that your Q70L operates at peak efficiency for miles beyond conventional oil change intervals.
Recommended AMSOIL Products
The following AMSOIL products are specifically selected to meet the exact specifications required for the 2018 Infiniti Q70L 3.7L engine and its various systems.
- AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil – The premier choice for this vehicle, offering 75% more engine protection against horsepower loss and wear, with a guaranteed service interval up to 25,000 miles or one year.
- AMSOIL Extended-Life 5W-30 100% Synthetic Motor Oil – A robust option providing 37% more cleaning power to keep the engine running smoother, with guaranteed protection for up to 20,000 miles.
- AMSOIL OE 5W-30 100% Synthetic Motor Oil – An economical yet high-performance solution that fights sludge and deposits while protecting turbochargers better than industry standards, suitable for those following OEM mileage schedules.
- AMSOIL 5W-30 100% Synthetic High-Mileage Motor Oil – Specifically engineered for vehicles over 75,000 miles, featuring enhanced detergents and anti-wear additives to reduce sludge by 67% and control oil consumption.
- AMSOIL Oil Filter – Provides a filtering efficiency of 99 percent at 20 microns, offering extended service life and greater capacity for small, wear-causing contaminants than competing filters.
- WIX Oil Filter – A premium media filter that offers improvements over original equipment manufacturer branded filters, ideal for pairing with the OE or High-Mileage motor oils.
- AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid – Designed to withstand the rigors of heavy towing, elevated temperatures, and challenging terrain while maintaining fluidity in sub-zero conditions.
- AMSOIL SEVERE GEAR® 75W-90 100% Synthetic Gear Lube – Provides advanced protection against wear and thermal runaway in the front and rear differentials, containing friction modifiers for limited-slip applications.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Offers excellent ABS and traction-control responsiveness with a stable viscosity over a wide temperature range, ensuring consistent braking performance.
- AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid – Reduces friction and helps seals remain soft to prevent leaks, formulated for quiet operation and excellent high-temperature protection.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A unique poly-organic acid formulation that protects all cooling system metals, gaskets, and hoses for up to 150,000 miles or 5 years.
Using the correct viscosity and formulation is critical for the 2018 Infiniti Q70L 3.7L engine. The engine requires 5.2 quarts of 5W-30 motor oil when changing the filter. Filling the engine beyond this capacity or using a viscosity that does not meet the VQ37VHR specifications can lead to increased internal pressure and reduced fuel economy. Our recommended oils are designed to handle the specific thermal loads of this Nissan-built V6, ensuring that the timing chain, which can be a point of concern in higher-mileage VQ engines, remains taut and well-lubricated.
Complete Fluid Recommendations by Category
To maintain the longevity and performance of your Infiniti, every fluid system requires specific attention. The cooling system for this model holds approximately 9.5 to 9.8 quarts depending on the specific configuration and whether a pressurized tank is included. AMSOIL Passenger Car & Light Truck Antifreeze & Coolant is an ideal choice here, as it is phosphate-free and compatible with the various metals used in Infiniti radiators and engines. This formulation prevents corrosion and scale buildup, which are common causes of overheating in vehicles that have seen years of use.
The automatic transmission is another critical component. For the 7-speed RE7R01A transmission, AMSOIL Signature Series Fuel-Efficient 100% Synthetic Automatic Transmission Fluid is highly recommended. A total fill requires 9.7 quarts. Standard fluid often degrades under the heat generated by shifting, leading to shudder and delayed engagement. Our synthetic transmission fluid resists oxidation and shear, ensuring smooth power delivery and extended transmission life. If you prefer a more budget-friendly option that still outperforms conventional fluids, the AMSOIL OE Fuel-Efficient 100% Synthetic Automatic Transmission Fluid is an excellent alternative, offering robust protection against wear.
Differential and transfer case lubrication is often overlooked but essential for rear-wheel drive and all-wheel drive variants. The front differential requires 1.4 pints of GL-5 compatible fluid. The rear differential holds 3 pints and specifically notes that synthetic oil is required. The transfer case capacity varies by configuration but generally requires a substantial amount of fluid. AMSOIL SEVERE GEAR 80W-90 100% Synthetic Gear Lube is engineered to protect these components from metal-to-metal contact, rust, and corrosion. It contains friction modifiers that are vital for limited-slip differentials, preventing the chattering and noise that can occur with improper lubrication. For extreme conditions or higher mileage, the AMSOIL SEVERE GEAR 75W-90 100% Synthetic Gear Lube or the AMSOIL SEVERE GEAR 75W-110 100% Synthetic Gear Lube provides even greater film strength.
AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid and AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid round out the essential maintenance fluids. The braking system relies on DOT 3 or DOT 4 specifications. AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid ensures consistent pedal feel and prevents boiling under heavy braking, which is crucial for a performance sedan like the Q70L. The power steering system benefits from AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid, which keeps the hydraulic seals pliable and prevents the fluid from becoming gummy over time. These fluids work in tandem to ensure the vehicle remains safe and responsive.
About the 2018 Infiniti Q70L
The 2018 Infiniti Q70L represents the pinnacle of Japanese luxury sedan engineering, blending opulent interior appointments with a driving character that appeals to both the comfort-seeking commuter and the performance enthusiast. Based on the Infiniti M platform, the Q70L is the long-wheelbase version of the standard Q70 sedan, offering significantly more rear-seat legroom, making it a favorite for chauffeur-driven situations and long-distance highway cruisers. The brand, a luxury division of Nissan Motor Co., has long been associated with the development of the legendary VQ series engines, a family that has been a staple in automotive history for decades.
At the heart of the 2018 Q70L is the 3.7-liter DOHC V6 engine, known internally as the VQ37VHR. This naturally aspirated powerhouse produces a robust 325 horsepower and 267 lb-ft of torque. Unlike many of its contemporaries that rely on turbochargers to achieve their output, this engine uses displacement and high-revving capability to deliver its power. This results in a linear and predictable throttle response that drivers often praise. The engine code VQ37VHR 3 is specific to this iteration, designed to meet rigorous emissions standards while maintaining the spirited nature that Infiniti owners expect. The VQ37 family is renowned for its durability, but like any high-performance internal combustion engine, it requires high-quality lubrication to keep the valvetrain and timing chain in top condition.
Owners of the Q70L typically value its smooth ride, advanced technology features, and distinctive styling. The vehicle sits in a competitive market segment against the Lexus ES, Acura TLX, and BMW 5 Series, distinguishing itself with a powerful V6 engine and a focus on rear-passenger luxury. The “L” designation stands for Long Wheelbase, a nod to the fact that the Q70L was specifically tailored to provide an executive-class experience. Despite its size, the Q70L maintains a sporty stance, aided by its independent suspension and precise steering. This combination makes it a versatile choice for those who want a car that can handle a daily commute and a spirited weekend drive with equal competence.
Common issues that owners of this vehicle encounter often relate to engine oil consumption and timing chain stretch as the vehicle accumulates high mileage. Over 100,000 miles, the VQ37 engine can develop a tendency to consume oil due to worn piston rings or valve stem seals. Additionally, the timing chain guides can wear out, leading to rattling noises upon cold starts. Using AMSOIL 5W-30 100% Synthetic High-Mileage Motor Oil can help mitigate these problems. The high-detergent formulations in AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil and AMSOIL Extended-Life 5W-30 100% Synthetic Motor Oil help keep the piston rings clean, preventing carbon buildup that can lead to oil consumption. Furthermore, the robust anti-wear additives in AMSOIL products provide a protective film on the timing chain tensioners and guides, extending their service life and maintaining the smooth, quiet operation that defines the Q70L experience.
Another area where the Q70L can show its age is in the transmission performance. As the vehicle ages, the fluid can degrade, leading to delayed shifts or shuddering. Regular fluid changes with a high-quality synthetic transmission fluid can restore smooth operation. The cooling system is also a critical area; while the VQ37 is a reliable engine, it operates at high temperatures, making a high-quality antifreeze essential to prevent corrosion in the aluminum radiator and engine block. By staying on top of these maintenance items with the recommended AMSOIL products, Q70L owners can ensure their luxury sedan continues to deliver the performance and comfort it was designed for, year after year.
Additional Maintenance Products
For those looking to add extra protection or improve fuel economy, AMSOIL offers a range of additives and care products. The AMSOIL P.i.® Performance Improver Gasoline Additive is an excellent gasoline additive that helps restore up to 14% horsepower and cleans GDI fuel injectors, addressing the carbon buildup that can occur in direct injection engines. For vehicles in storage, the AMSOIL Gasoline Stabilizer keeps fuel fresh for up to 12 months, preventing varnish and gum buildup. AMSOIL Engine Fogging Oil is ideal for protecting internal components during long periods of inactivity. For those who enjoy washing their vehicles, the AMSOIL Miracle Wash Waterless Wash and Wax Spray offers a convenient way to clean and protect the paint without scratching, while the AMSOIL Exterior Ceramic Spray provides long-lasting UV protection and a deep shine.
By combining these products with the recommended fluids, you create a comprehensive maintenance regimen that protects your 2018 Infiniti Q70L from the inside out. Whether you are extending service intervals to maximize the value of your synthetic lubricants or simply ensuring your vehicle is as smooth and efficient as the day it rolled off the lot, AMSOIL provides the solution. With their rigorous third-party testing and driver-approved formulas, these products give you the confidence that your investment is being properly cared for.