Infiniti Transmission Fluid: A Deep Dive

Many Infiniti owners, particularly those with hybrid models, often find themselves researching transmission fluid, especially as their vehicles age and approach or exceed their warranty periods. The question often arises: "Does Infiniti have a TSB (Technical Service Bulletin) for transmission fluid issues?" While specific TSBs vary by model and year, understanding the importance of the correct transmission fluid and the potential benefits of an upgrade can be incredibly valuable. This article delves into the world of Infiniti transmission fluids, drawing on real-world experiences to highlight the impact of choosing the right product.

Understanding Transmission Fluid and its Importance

The transmission fluid in your Infiniti is a critical component responsible for a multitude of tasks. It lubricates moving parts, reduces friction and wear, cools the transmission, and acts as a hydraulic fluid to engage gears. Over time, this fluid can degrade due to heat, contamination from clutch material and metal shavings, and general wear and tear. This degradation can lead to a range of problems, including rough shifting, delayed engagement, increased noise, and even transmission failure. For Infiniti hybrids, with their complex dual-clutch systems (both dry and wet), maintaining the integrity of the transmission fluid is even more paramount.

The Matic S Standard and Fluid Compatibility

Infiniti, like many manufacturers, specifies a particular type of transmission fluid for its vehicles. For many models, including the Q50 hybrid, the recommended fluid is often referred to as Matic S. This fluid is specifically formulated to meet the stringent requirements of Infiniti transmissions, ensuring optimal performance and longevity. However, obtaining genuine Matic S fluid can sometimes be a challenge or prohibitively expensive, as one owner discovered when faced with purchasing 40-litre drums at a substantial cost.

This leads to the crucial question of compatibility. Can alternative fluids be used? The answer is yes, but with caution and thorough research. Many reputable aftermarket manufacturers produce synthetic automatic transmission fluids (ATFs) that are designed to be compatible with, or meet the specifications of, OEM fluids like Matic S. In the case mentioned, Amsoil Fuel Efficient Synthetic ATF (the blue bottle) was chosen for its stated compatibility with Matic S.

Real-World Experience: The Amsoil Q50 Hybrid Upgrade

One Infiniti Q50 hybrid owner, facing the end of their warranty and the high cost of OEM fluid, decided to switch to Amsoil Fuel Efficient Synthetic ATF. Over several weekends, they performed multiple drain-and-fill procedures, replacing approximately 15 litres of fluid. This extensive flush was undertaken to ensure the removal of as much clutch material as possible from the hybrid system's intricate clutch setup.

Noticeable Improvements After the Fluid Change

The results of this fluid change were, according to the owner, immediately apparent and highly satisfying. The most striking observation was a significant reduction in transmission noise and a noticeable improvement in smoothness. The transmission exhibited less "hunting," a common issue where the gearbox struggles to find the optimal gear, particularly during light throttle coasting. This hunting was especially pronounced when transitioning between the electric motor and the internal combustion engine (ICE).

Another significant improvement was observed during start-up. Previously, on the first start of the day, there was a slight, half-second delay before the car would begin to roll when shifted into drive. After the Amsoil fluid change, this delay vanished. The engagement from PARK to DRIVE became seamless and smooth, to the point where the owner couldn't feel the transmission engaging, even when the ICE was running.

Performance Under Load

The benefits extended to more demanding driving scenarios. During a spirited country drive, which included an "Italian tune-up" (a vigorous drive to clear out carbon deposits), the Q50 hybrid performed exceptionally well, even keeping pace with a Porsche Cayman S on twisty roads. This exhilarating experience highlighted the transmission's newfound responsiveness.

Furthermore, when driving solely on electric power and requiring a sudden acceleration for an overtake, especially on an incline, the transmission's response was markedly improved. With the old fluid, there was a slight hesitation before the ICE motor engaged. With the new Amsoil fluid, this delay was virtually eliminated, leading to more immediate and confident acceleration.

The Bottom Line: Early Intervention is Key

The owner's concluding sentiment was a strong recommendation to have performed the transmission fluid change much earlier in their ownership of the hybrid. The positive impact on the vehicle's performance, smoothness, and responsiveness was substantial. This real-world account underscores the importance of not neglecting transmission fluid maintenance, even if your vehicle is still within its warranty period.

When to Consider a Transmission Fluid Change

While there isn't a universal mileage interval for all Infiniti models, several indicators suggest it might be time for a transmission fluid change:

• Rough Shifting: If you notice jerky or hesitant gear changes.
• Delayed Engagement: A noticeable lag when shifting from Park to Drive or Reverse.
• Transmission Slipping: The engine revs up, but the car doesn't accelerate proportionally.
• Unusual Noises: Whining, clunking, or grinding sounds from the transmission.
• Fluid Appearance: If you can check the transmission fluid (some Infinitis have sealed transmissions), look for a dark, burnt smell, or the presence of debris.
• Manufacturer Recommendations: Always consult your Infiniti owner's manual for the recommended service intervals.
• High Mileage: Even without obvious symptoms, consider a fluid change around the 80,000-100,000 mile mark as a preventative measure.

Infiniti TSBs: What You Need to Know

Technical Service Bulletins (TSBs) are issued by manufacturers to inform dealerships and technicians about known issues and provide repair procedures. While it's difficult to provide a comprehensive list of all Infiniti transmission-related TSBs without knowing your specific model and year, it's always advisable to:

• Check with Your Dealership: The most reliable way to determine if a TSB applies to your vehicle is to contact an authorized Infiniti dealership with your VIN. They can check their system for any outstanding or relevant TSBs.
• Online Resources: Some automotive forums and websites compile lists of TSBs. However, always verify this information with a dealership.
• Symptoms Alignment: If you are experiencing specific transmission problems, research if those symptoms are commonly addressed by Infiniti TSBs for your model.

Choosing the Right Transmission Fluid: Key Considerations

When selecting a transmission fluid, especially if opting for an aftermarket product, consider the following:

Frequently Asked Questions

Q1: Can I use a universal ATF in my Infiniti?

While some "universal" ATFs claim broad compatibility, it is strongly advised against using them in your Infiniti unless they explicitly state compatibility with your specific Matic fluid requirement. Using an incompatible fluid can cause significant damage to your transmission.

Q2: How often should I change my Infiniti's transmission fluid?

Consult your owner's manual for the manufacturer's recommended interval. Generally, for many Infinitis, this can range from 60,000 to 100,000 miles, but this can vary. Driving conditions and habits can also influence the optimal change interval.

Q3: Is it necessary to replace the transmission filter during a fluid change?

If your Infiniti's transmission has a serviceable filter, it is highly recommended to replace it whenever you change the fluid. The filter traps debris and contaminants, and replacing it ensures the fluid remains clean for longer. However, some modern transmissions have "lifetime" filters that are not designed for regular replacement.

Q4: My Infiniti transmission is sealed. Can I still change the fluid?

Many modern transmissions, including some in Infinitis, are sealed units, meaning they don't have a traditional dipstick. In such cases, fluid changes are typically performed via a fill plug, often requiring specialized equipment and knowledge. It's best to have this done by a qualified mechanic or dealership.

Q5: What are the risks of not changing transmission fluid?

Neglecting transmission fluid maintenance can lead to increased wear on transmission components, overheating, rough shifting, slipping gears, and ultimately, costly transmission failure. The fluid loses its lubricating and cooling properties over time.

Conclusion

The experience of the Q50 hybrid owner clearly demonstrates that the right transmission fluid can make a world of difference in the performance, smoothness, and overall driving enjoyment of your Infiniti. While specific TSBs should always be confirmed with a dealership, understanding the importance of fluid quality, compatibility, and timely maintenance is crucial for every Infiniti owner. Whether you're experiencing subtle issues or simply looking to maintain optimal performance, a proactive approach to transmission fluid care is a wise investment in your vehicle's longevity.