Introduction

In this article, we will dive into the inner workings of a continuously variable transmission (CVT) used in Nissan vehicles. Specifically, we will explore why some Nissan CVTs fail and the various components of the transmission. Whether you are a car enthusiast or a Nissan owner concerned about potential transmission issues, this article will provide an in-depth analysis of the topic.

The Components of a Nissan CVT

A Nissan CVT consists of several key components that work together to ensure smooth and efficient transmission operation. Let’s take a closer look at each component:

  1. Torque Converter: Similar to a traditional automatic transmission, a Nissan CVT also features a torque converter. This component helps convert torque from the engine into a rotational motion for the transmission.

  2. Transaxle Configuration: Nissan CVTs, like the one featured in the Nissan Murano, are designed in a transaxle configuration for front-wheel drive vehicles. This configuration includes a transmission cooler to regulate temperature.

  3. Manual Valve: Located at the top of the transmission, the manual valve connects to the gear selector on the console. This valve determines the selected gear and controls the flow of fluid throughout the transmission.

  4. Variators: The transmission casing houses the variators, which are responsible for altering the pulley ratio. These pulleys, along with a belt, allow for seamless gear transitions.

Common Issues with Nissan CVTs

While Nissan CVTs generally provide a smooth driving experience, there have been reports of transmission failures in certain models. Understanding these issues can help owners identify potential problems and seek timely repairs or maintenance. Here are some common problems associated with Nissan CVTs:

  1. Overheating: One of the primary causes of Nissan CVT failure is overheating. Continuous use of the transmission without proper cooling can lead to premature wear and damage to internal components.

  2. Belt Slippage: The belt connecting the variators in a CVT is essential for transmitting power. If this belt slips or experiences excessive wear, it can result in a loss of power and overall transmission failure.

  3. Fluid Contamination: Contaminated transmission fluid can cause significant damage to a Nissan CVT. Dirt, debris, or metal particles in the fluid can clog the hydraulic circuits and prevent efficient operation.

  4. Control Module Issues: Problems with the transmission control module (TCM) can also contribute to CVT failures. The TCM regulates fluid pressure, gear ratios, and other transmission functions. Any malfunctions in this module can result in improper operation and potential damage.

Disassembling a Nissan CVT

To gain a better understanding of the inner workings of a Nissan CVT, let’s walk through a step-by-step process of disassembling the transmission:

  1. Removing External Components: Start by disconnecting and removing external components such as hoses, coolers, and electrical connectors from the transmission.

  2. Valve Body Removal: The valve body, located at the bottom of the transmission, controls fluid flow throughout the system. Remove the valve body to access the internal hydraulic circuits.

  3. Filter Removal: The transmission filter, similar to an oil filter in regular cars, should be removed and inspected for any debris or contaminants.

  4. Electrical Connectors and Control Rod: Detach the electrical connectors and control rod that connect the transmission shifter to the manual valve. These components control the transmission’s various modes and gear selections.

  5. Removing the Valve Body: Unscrew the 10-millimeter bolts securing the valve body and lift it out of the transmission casing. Examine the valve body for any signs of damage or wear.

  6. Exploring the Control System: Study the hydraulic and electrical aspects of the CVT control system. The transmission control module (TCM) and various solenoids and valves play vital roles in regulating fluid flow and gear ratios.

  7. Examining the Inside of the Transmission: After removing the bell housing, the input shaft and variator mechanism become visible. Take note of these components, including the intermediate gear and the final drive differential.

  8. Disassembling the Oil Pump: Remove the housing and hex bolts to expose the oil pump. The oil pump is responsible for circulating and pressurizing the transmission fluid.

  9. Analyzing the Planetary Gear Set: Similar to automatic transmissions, a CVT includes a planetary gear set. This gear set allows for gear ratio adjustments and provides the reverse function.

  10. Exploring the Continuously Variable Transmission: With the CVT turned over, observe the input and output pulleys connected by a steel belt. This belt enables seamless gear transitions in the transmission.

Conclusion

Understanding the complexities and potential issues of Nissan CVTs is essential for both car enthusiasts and Nissan owners. This article provided a comprehensive overview of the inner workings of a Nissan CVT, including a detailed breakdown of its components and a step-by-step guide to disassembling the transmission. By familiarizing yourself with these details, you can better identify and address any transmission problems that may occur, ensuring a smooth and enjoyable driving experience.