2015 Nissan Murano Transmission Problems

Nissan
2015 Nissan Murano Transmission Problems

The 2015 Nissan Murano, while praised for its styling and comfortable ride, has become notorious for transmission issues, particularly related to its Continuously Variable Transmission (CVT). This article will delve into the common problems experienced, the underlying causes, and potential solutions for the experienced DIYer.

Understanding the CVT (RE0F10A/JF017E)

Before diving into the specific problems, it’s crucial to understand how a CVT works. Unlike traditional automatic transmissions with fixed gear ratios, a CVT uses a belt and pulley system to offer an infinite range of ratios. This allows the engine to operate at its most efficient RPM, theoretically improving fuel economy and providing smoother acceleration. The 2015 Murano primarily uses the RE0F10A (JF011E) or JF017E CVT, depending on the engine (typically the 3.5L V6). However, this design, while innovative, also introduces unique failure points.

Key Components & Their Roles

  • Belt: The primary component responsible for transmitting power between the input and output pulleys. Often made of steel bands, its integrity is critical for smooth operation.
  • Pulleys: Two sets of cone-shaped pulleys (input and output) whose effective diameter changes based on hydraulic pressure. This varying diameter creates the "infinite" gear ratios.
  • Valve Body: The control center of the CVT. It contains a network of solenoids and valves that regulate hydraulic pressure to the pulleys, clutch, and other components.
  • Transmission Control Module (TCM): A computer that receives input from various sensors (e.g., engine speed, throttle position, wheel speed) and controls the valve body to achieve the desired gear ratio.
  • Torque Converter: Functions similarly to a traditional automatic transmission, providing a fluid coupling between the engine and the CVT.
  • Oil Pump: Supplies the hydraulic pressure necessary for the CVT to operate. Adequate fluid pressure is essential for proper function and longevity.

Common 2015 Murano CVT Problems

The following are the most frequently reported issues with the 2015 Murano's CVT:

1. Shuddering and Hesitation

Symptoms: A noticeable shaking or vibrating sensation, particularly during acceleration from a stop or at low speeds. The car may feel sluggish or hesitant to respond to throttle input.

Causes: This is often the first sign of CVT problems. It can be caused by:

  • Degraded Transmission Fluid: CVT fluid is specifically formulated for the unique demands of a CVT. Over time, it degrades, losing its lubricating and frictional properties. This can lead to slippage and shuddering.
  • Valve Body Issues: Worn or malfunctioning solenoids in the valve body can cause incorrect hydraulic pressure, leading to erratic shifting and shuddering. Internal leaks within the valve body can also be a culprit.
  • Belt Slippage: As the belt wears, it can begin to slip on the pulleys, especially under load. This slippage generates heat and further accelerates wear.
  • Torque Converter Problems: A failing torque converter can also contribute to shuddering, although this is less common than CVT-specific issues.

Potential Solutions:

  • CVT Fluid Change: This is the first and most important step. Use only Nissan-recommended CVT fluid (NS-3). A simple drain and fill is often insufficient. A complete fluid exchange using a specialized machine is highly recommended.
  • Valve Body Replacement/Refurbishment: If a fluid change doesn't resolve the issue, the valve body may need to be replaced or refurbished. This is a more complex repair that often requires specialized tools and knowledge.
  • Belt Replacement: Replacing the belt is a major repair that typically requires removing the transmission. It's generally only recommended if the belt is visibly damaged or severely worn.
  • Torque Converter Replacement: If diagnostics point to the torque converter, it will need to be replaced.

2. Overheating

Symptoms: The transmission temperature warning light illuminates, or the vehicle enters a limp mode (reduced power and speed). You might also notice a burning smell coming from the engine compartment.

Causes: CVTs generate significant heat during operation. Overheating can be caused by:

  • Low Transmission Fluid Level: Insufficient fluid reduces the transmission's ability to dissipate heat.
  • Clogged Transmission Cooler: The transmission cooler helps to remove heat from the CVT fluid. A clogged cooler restricts fluid flow and reduces cooling efficiency.
  • Excessive Load: Towing heavy loads or driving aggressively can put excessive strain on the CVT, generating more heat than it can dissipate.
  • Internal Component Failure: Worn belts, pulleys, or other internal components can generate excessive friction, leading to overheating.

Potential Solutions:

  • Check and Top Off Fluid Level: Ensure the CVT fluid is at the correct level according to the manufacturer's specifications.
  • Flush Transmission Cooler: Use a specialized flushing tool to remove any debris or contaminants from the transmission cooler.
  • Inspect and Replace Thermostat: If the thermostat is stuck closed, it will prevent the CVT fluid from circulating through the cooler.
  • Address Underlying Mechanical Issues: If overheating is caused by internal component failure, the transmission may need to be rebuilt or replaced.
  • Consider an Auxiliary Transmission Cooler: For those who frequently tow or drive in hot climates, installing an auxiliary transmission cooler can help to improve cooling efficiency and prevent overheating.

3. Transmission Slipping

Symptoms: The engine revs up without a corresponding increase in vehicle speed. The transmission may also shift erratically or fail to engage gears properly.

Causes: Slipping is a serious symptom indicating significant internal damage. Common causes include:

  • Worn Belt and Pulleys: Extensive wear on the belt and pulleys can lead to slippage, especially under load.
  • Valve Body Malfunctions: Incorrect hydraulic pressure due to valve body issues can prevent the CVT from properly engaging the pulleys.
  • Internal Seal Leaks: Leaks within the CVT can reduce hydraulic pressure, leading to slippage.
  • Severe Fluid Contamination: Contaminated fluid can damage internal components and reduce the CVT's ability to grip the pulleys.

Potential Solutions:

  • CVT Fluid Change (as a diagnostic): While unlikely to fix severe slipping, a fluid change can sometimes temporarily improve performance and help determine the extent of the damage.
  • Transmission Rebuild or Replacement: In most cases, transmission slipping requires a complete rebuild or replacement. This is a complex and expensive repair that is best left to a qualified transmission specialist.

4. Limp Mode

Symptoms: The vehicle enters a reduced power mode, limiting speed and acceleration. This is often accompanied by a warning light on the dashboard.

Causes: Limp mode is a safety mechanism designed to protect the transmission from further damage. It's triggered by various faults, including:

  • Overheating: As mentioned above, overheating can trigger limp mode.
  • Sensor Malfunctions: Faulty sensors can provide incorrect data to the TCM, causing it to enter limp mode.
  • Valve Body Problems: Erratic shifting or incorrect hydraulic pressure can also trigger limp mode.
  • Internal Transmission Damage: Severe internal damage can also activate the limp mode.

Potential Solutions:

  • Diagnostic Scan: Use an OBD-II scanner to retrieve diagnostic trouble codes (DTCs). These codes can provide valuable information about the cause of the limp mode.
  • Address Underlying Issues: Repair or replace any faulty sensors, valves, or other components that are causing the problem.
  • Clear Diagnostic Codes: After making repairs, clear the diagnostic codes and test drive the vehicle to ensure that the limp mode has been resolved.

Preventative Maintenance

The best way to avoid CVT problems is to follow a strict preventative maintenance schedule. This includes:

  • Regular CVT Fluid Changes: Change the CVT fluid every 30,000 miles or as recommended by the manufacturer. Always use the correct Nissan NS-3 fluid.
  • Transmission Cooler Inspection: Inspect the transmission cooler for leaks or clogs and clean or replace it as needed.
  • Avoid Overloading: Do not exceed the vehicle's towing capacity and avoid aggressive driving habits.
  • Monitor Transmission Temperature: If possible, monitor the transmission temperature, especially when towing or driving in hot conditions.

Conclusion

The 2015 Nissan Murano's CVT can be problematic, but understanding the common issues and implementing preventative maintenance can significantly extend its lifespan. While some repairs, like fluid changes, are within the scope of a skilled DIYer, more complex issues like valve body replacement or transmission rebuilds are best left to experienced professionals. Remember to always use the correct fluids and parts, and consult with a qualified mechanic if you are unsure about any aspect of the repair process. Proper diagnosis is key! Using a scan tool capable of reading Nissan-specific transmission codes is essential for accurate troubleshooting.

Related Posts