2000 Nissan Xterra Transmission For Sale

The 2000 Nissan Xterra, a rugged and capable SUV, relied on a robust transmission system to deliver power to the wheels. Whether you're considering purchasing a used 2000 Xterra transmission or simply curious about its inner workings, understanding the specifics of this unit is crucial. This article provides a technical overview of the 2000 Nissan Xterra transmission, covering its design, operation, common issues, and considerations for replacement.

Transmission Options: Automatic and Manual

The 2000 Xterra was offered with both automatic and manual transmission options, catering to different driving preferences. The most common automatic transmission was the RE4R01A, a 4-speed unit renowned for its reliability. The manual transmission was a 5-speed unit, offering greater driver control and potentially better fuel economy. Both transmissions were designed to handle the output of the Xterra's engine, typically a 3.3L V6.

RE4R01A Automatic Transmission: A Deeper Dive

The RE4R01A is a hydraulically controlled, electronically assisted 4-speed automatic transmission. It relies on a complex system of valves, solenoids, and fluid pressure to select the appropriate gear. Understanding its components is key to diagnosing potential issues.

Torque Converter: This fluid coupling connects the engine to the transmission, allowing the engine to continue running even when the vehicle is stopped. Inside, an impeller driven by the engine circulates fluid, which then spins a turbine connected to the transmission's input shaft. This process allows for smooth starts and dampens vibrations. A lock-up clutch within the torque converter can engage at higher speeds, providing a direct mechanical connection for improved efficiency.
Planetary Gear Sets: The transmission utilizes multiple planetary gear sets to achieve different gear ratios. Each set consists of a sun gear, planet gears, a ring gear, and a carrier. By selectively holding or releasing different components, the transmission can engage different gear ratios, allowing for acceleration, cruising, and climbing.
Valve Body: The valve body is the "brain" of the automatic transmission. It's a complex network of channels, valves, and solenoids that control the flow of transmission fluid to different parts of the transmission. These valves are responsible for shifting gears and regulating line pressure.
Solenoids: Electrically controlled solenoids in the valve body act as on/off switches, directing fluid flow based on signals from the vehicle's Transmission Control Module (TCM). These solenoids control shift timing, torque converter lock-up, and other critical functions.
Transmission Control Module (TCM): The TCM receives input from various sensors, including vehicle speed, engine speed, throttle position, and transmission fluid temperature. Based on this information, the TCM determines the optimal gear to engage and controls the solenoids accordingly.

Proper lubrication is vital for the RE4R01A's longevity. Regular fluid changes with the recommended Nissan Matic D or equivalent fluid are essential. Low fluid levels or contaminated fluid can lead to slipping, harsh shifting, and eventual transmission failure.

5-Speed Manual Transmission: Simplicity and Control

The 5-speed manual transmission in the 2000 Xterra offers a more direct driving experience. While simpler in some ways than the automatic, it still involves intricate mechanical components.

Clutch: The clutch disengages the engine from the transmission, allowing the driver to shift gears. It consists of a pressure plate, clutch disc, and flywheel. Wear and tear on the clutch disc is common, especially with aggressive driving.
Gears and Shafts: The transmission contains multiple gears and shafts that mesh together to create different gear ratios. Synchronizers are used to match the speed of the gears before they engage, preventing grinding and ensuring smooth shifts.
Shift Linkage: The shift linkage connects the gear shift lever to the transmission, allowing the driver to select the desired gear. Worn or misadjusted linkage can lead to difficulty shifting or popping out of gear.

Manual transmissions typically require less maintenance than automatics, but regular gear oil changes are still important. Using the correct type of gear oil, typically a GL-4 rated oil, is crucial for protecting the gears and synchronizers.

Common Problems and Troubleshooting

Both the automatic and manual transmissions in the 2000 Xterra are generally reliable, but they are not immune to problems. Knowing the common issues can help you diagnose potential problems and make informed decisions about repairs or replacement.

Automatic Transmission Problems:

Slipping: Slipping occurs when the transmission fails to properly engage a gear, resulting in a loss of power and increased engine RPM. This can be caused by low fluid, worn clutches, or a malfunctioning valve body.
Harsh Shifting: Rough or jerky shifts can indicate a problem with the valve body, solenoids, or transmission fluid.
Delayed Engagement: A delay in engaging a gear, especially when shifting from Park to Drive or Reverse, can suggest low fluid, a failing torque converter, or internal transmission damage.
Overheating: Overheating can damage the transmission's internal components. Causes include low fluid, heavy towing, or a malfunctioning transmission cooler.
Transmission Fluid Leaks: Leaks can occur at the seals, gaskets, or torque converter. Addressing leaks promptly is essential to prevent low fluid levels and transmission damage.

Manual Transmission Problems:

Clutch Slipping: A slipping clutch results in a loss of power and increased engine RPM, especially during acceleration. This is usually caused by a worn clutch disc.
Difficulty Shifting: Difficulty shifting into gear can indicate a problem with the shift linkage, synchronizers, or clutch.
Grinding: Grinding when shifting suggests worn synchronizers.
Popping Out of Gear: The transmission disengaging from the selected gear can be caused by worn gears, shift linkage issues, or internal damage.
Noise: Unusual noises, such as whining or grinding, can indicate worn bearings or gears.

Regular maintenance, including fluid changes and inspections, can help prevent many of these problems. When troubleshooting, always check the fluid level and condition first. Scan for diagnostic trouble codes (DTCs) using an OBD-II scanner, as these codes can provide valuable clues about the source of the problem. A professional transmission diagnostic can pinpoint the exact issue and recommend the appropriate repair.

Considering a Replacement Transmission

If your 2000 Xterra transmission is exhibiting severe problems, such as significant slipping, loud noises, or internal damage, replacing it may be the most cost-effective solution. When considering a replacement, you have several options:

New Transmission: A new transmission is the most expensive option, but it offers the peace of mind of knowing that all the components are new and under warranty.
Remanufactured Transmission: Remanufactured transmissions are rebuilt to meet or exceed original factory specifications. They typically come with a warranty and offer a good balance between price and reliability. Ensure the remanufacturer has a good reputation and offers a comprehensive warranty.
Used Transmission: A used transmission is the least expensive option, but it also carries the most risk. The condition of a used transmission can be difficult to assess, and it may have a limited lifespan.
When purchasing a used transmission, try to obtain information about its history, such as the mileage of the vehicle it came from and the reason for removal.
Consider having a mechanic inspect the used transmission before installation.

Before purchasing a replacement transmission, verify the part number to ensure compatibility with your specific 2000 Xterra model. Different trim levels and engine options may require different transmissions. Consider factors such as the transmission's warranty, mileage (if used), and the seller's reputation. A qualified mechanic can provide valuable advice and perform the installation, ensuring proper operation and minimizing the risk of future problems.

In conclusion, the 2000 Nissan Xterra transmission, whether automatic or manual, is a crucial component for delivering power and performance. Understanding its design, operation, common issues, and replacement options empowers you to make informed decisions about maintenance, repairs, and upgrades. By paying attention to the transmission's health and addressing problems promptly, you can keep your Xterra running smoothly for years to come.