The Command-Trac four-wheel-drive system found in the Jeep Grand Cherokee (WJ) offers drivers a choice between two-wheel drive for everyday commuting and fuel efficiency, and four-wheel drive for off-road adventures or challenging weather conditions. Drivers can shift between these modes using a selector lever. This system provides various configurations for handling diverse terrains, including 4-Hi for general off-roading and 4-Lo for traversing particularly difficult landscapes like steep inclines or deep mud. The optional Quadra-Trac I, a full-time four-wheel-drive system automatically adjusting power distribution between axles, was also available for this model.
Offering this choice enhances both vehicle versatility and fuel economy. For the WJ generation Grand Cherokee (1999-2004), this feature broadened its appeal to consumers seeking both on-road comfort and off-road capability. This system’s flexibility catered to diverse driving needs and preferences, making it a popular choice for drivers who required both on-road civility and off-road prowess. The evolution of four-wheel-drive systems within the Jeep brand reflects a continuous improvement in handling various driving conditions and contributing to the brand’s legacy of off-road dominance.
Understanding the capabilities and operational nuances of these systems is crucial for maximizing the WJ’s performance and safety. The following sections will delve into the specifics of each mode, covering best practices, maintenance considerations, and potential troubleshooting tips.
1. 2WD
The “2WD” or two-wheel drive mode within the Jeep Grand Cherokee (WJ) “select-drive” system plays a crucial role in optimizing fuel efficiency and on-road handling. By delivering power solely to the rear wheels, this mode reduces drivetrain friction and parasitic losses inherent in four-wheel-drive operation. This results in improved fuel economy during regular commuting and highway driving. Furthermore, 2WD contributes to a lighter, more responsive steering feel, enhancing maneuverability in urban environments and on paved roads. Selecting 2WD on dry pavement ensures optimal tire wear and minimizes unnecessary stress on drivetrain components. For example, highway driving in 2WD significantly reduces fuel consumption compared to 4WD, offering tangible cost savings over time.
The ability to seamlessly switch between 2WD and 4WD modes through the “select-drive” system provides a practical balance between efficiency and capability. This feature allows drivers to adapt to changing road conditions and driving needs. While 4WD offers superior traction in challenging terrains, prolonged use on dry pavement can lead to increased fuel consumption and drivetrain wear. Conversely, exclusive reliance on 2WD limits off-road capabilities, potentially leaving the vehicle vulnerable in inclement weather or challenging terrains. Judicious use of 2WD maximizes its benefits without compromising safety or performance. For example, a WJ owner might utilize 2WD during a daily commute and then switch to 4WD when encountering snowy roads or venturing onto an unpaved trail.
Understanding the role and implications of 2WD within the “select-drive” system is critical for optimal WJ operation. This knowledge allows drivers to make informed decisions about mode selection based on driving conditions, maximizing both fuel efficiency and vehicle longevity. Failure to utilize 2WD appropriately can lead to unnecessary fuel expenditure and increased drivetrain wear. Recognizing the limitations of 2WD in off-road or low-traction situations is equally important for safe and effective vehicle operation. The selection of the correct drive mode underscores the versatility and adaptability of the WJ platform.
2. 4WD High
“4WD High” constitutes a crucial element within the “select drive” system of the Jeep Grand Cherokee (WJ). This mode engages all four wheels, providing enhanced traction and stability in various on- and off-road scenarios, distinguishing it from the two-wheel-drive mode. Understanding its functionality is essential for maximizing the WJ’s versatility and adapting to changing driving conditions.
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Enhanced Traction
4WD High distributes power to all four wheels, significantly improving traction on slippery surfaces such as gravel, loose dirt, snow, or wet pavement. This enhanced grip allows for safer and more controlled vehicle handling in adverse weather conditions. For instance, navigating a snow-covered incline or traversing a muddy trail becomes more manageable and predictable with 4WD High engaged. The improved traction minimizes wheel slippage and enhances directional stability, promoting confident vehicle control.
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Moderate Off-Roading
While not designed for extreme off-road challenges, 4WD High proves effective in moderate off-road situations. It facilitates traversing uneven terrain, navigating shallow mud or sand, and overcoming obstacles that would pose difficulties for 2WD. For example, a forest trail or a rocky beach becomes accessible with 4WD High, expanding the WJ’s capabilities beyond paved roads. However, it is crucial to avoid high speeds in 4WD High, especially on dry pavement, to prevent drivetrain strain and maintain vehicle control.
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Fuel Efficiency Considerations
Engaging 4WD High results in higher fuel consumption compared to 2WD due to the increased drivetrain load. This increased demand on the engine stems from the power distribution to all four wheels. While the enhanced traction and stability offer significant benefits in challenging conditions, drivers should prioritize 2WD on dry pavement to maximize fuel economy. Unnecessary use of 4WD High on dry surfaces not only increases fuel costs but also contributes to accelerated drivetrain wear.
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Part-Time System Integration
The “select drive” system in the WJ is a part-time 4WD system, meaning it requires manual shifting between 2WD and 4WD modes. This contrasts with full-time systems that automatically adjust power distribution. Drivers must actively select 4WD High when conditions demand enhanced traction and revert to 2WD when conditions improve. This manual control allows for greater driver involvement and control over the vehicle’s performance and fuel efficiency.
The “4WD High” mode, within the context of the WJ’s “select drive” system, provides a critical balance between enhanced traction and fuel efficiency. Its judicious use ensures safe and effective vehicle operation in various driving scenarios, contributing to the WJ’s versatility and adaptability. Understanding its operational parameters and limitations is fundamental for maximizing its potential while minimizing unnecessary wear and fuel consumption.
3. 4WD Low
4WD Low, integral to the Jeep Grand Cherokee (WJ) “select drive” system, significantly amplifies torque output, enabling the vehicle to navigate extreme off-road conditions. This functionality results from the transfer cases low-range gear ratio, multiplying engine torque and reducing output speed. This mechanical advantage allows for controlled ascents and descents on steep inclines, traversing deep mud or sand, and maneuvering over large obstacles, extending the WJ’s capabilities beyond the limitations of 4WD High and “2WD.” For example, tackling a deeply rutted trail or crawling over rocks necessitates the amplified torque provided by 4WD Low. Improper use, such as engaging it on high-traction surfaces, can cause drivetrain damage due to excessive torque application.
This low-range gearing proves particularly crucial in situations demanding precise throttle control at low speeds. It allows for maintaining momentum without excessive wheelspin, essential for navigating challenging terrain while minimizing the risk of becoming stuck or losing control. Furthermore, engine braking is enhanced in 4WD Low, offering superior control during descents. This helps prevent uncontrolled acceleration, promoting safer off-road driving. Imagine descending a steep, rocky decline; 4WD Low aids in controlled descent, reducing reliance on brake application and minimizing the potential for skidding.
Utilizing 4WD Low effectively requires understanding its operational parameters. Engagement should occur only when the vehicle is stationary or at very low speeds, and exclusively on loose or slippery surfaces where the added torque and reduced speed are beneficial. Switching to or from 4WD Low while moving at higher speeds can damage the transfer case. Regular maintenance of the select drive system, including fluid changes and inspections, is crucial for ensuring the longevity and reliability of 4WD Low functionality. Neglecting this maintenance can lead to premature wear, potentially compromising off-road capability and necessitating costly repairs. The combination of 4WD Low and the overall “select drive” system enables the WJ to handle a wide range of driving conditions, solidifying its reputation as a versatile and capable off-road vehicle.
4. Neutral
The “Neutral” position within the Jeep Grand Cherokee (WJ) “select drive” system serves a distinct and crucial function, primarily related to flat towing. Disengaging the drivetrain from the wheels allows the vehicle to roll freely without engine power. This is essential for towing the WJ behind another vehicle, as it prevents damage to the transmission and transfer case. Without this neutral setting, the drivetrain components would rotate while being towed, leading to excessive wear and potential mechanical failure. Therefore, understanding the proper use of “Neutral” is vital for preserving the integrity of the WJ’s drivetrain during towing.
Selecting “Neutral” requires a specific procedure, typically involving shifting the transmission into neutral, then engaging the transfer case into its neutral position. This decoupling action isolates the drivetrain from the wheels, enabling safe towing. Overlooking this step can have significant negative consequences. For instance, towing a WJ with the “select drive” system engaged, even with the transmission in neutral, can cause severe damage to the transfer case due to the continued rotation of internal components. This highlights the critical importance of adhering to the correct procedure for placing the “select drive” system into “Neutral” before towing.
While “Neutral” is primarily associated with flat towing, its proper utilization also extends to specific maintenance procedures and emergency situations. For example, some diagnostic procedures might require the drivetrain to be disengaged. Similarly, if the vehicle experiences a mechanical failure that prevents it from being driven, towing with the “select drive” in “Neutral” becomes necessary. Therefore, understanding this functionality contributes not only to safe towing practices but also to effective maintenance and emergency preparedness. Failing to grasp its significance risks potential damage and underscores the importance of comprehensive knowledge regarding the “select drive” system’s operation within the WJ platform.
5. Part-Time System
The Jeep Grand Cherokee (WJ)’s “select drive” system functions as a part-time four-wheel-drive setup. This design requires drivers to actively select between two-wheel drive (2WD) and four-wheel drive (4WD), unlike full-time systems that automatically adjust power distribution. Understanding this part-time functionality is crucial for optimizing performance, fuel efficiency, and drivetrain longevity. The following facets illustrate the key components and implications of this system.
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Manual Shift Control
The part-time nature mandates driver intervention for mode changes. A transfer case lever or electronic switch allows selection between 2WD and 4WD, giving the driver direct control over power distribution. This manual control allows for adapting to specific driving conditions, conserving fuel in optimal circumstances, and engaging 4WD only when needed. For example, dry pavement driving necessitates 2WD for fuel efficiency, while snowy or off-road conditions require switching to 4WD.
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Drivetrain Binding on Dry Pavement
Operating a part-time 4WD system on high-traction surfaces like dry pavement can cause drivetrain binding. This occurs because the front and rear axles rotate at slightly different speeds during turns. In 4WD, this difference creates stress within the drivetrain, potentially leading to premature wear and damage. Consequently, 2WD remains the preferred mode for dry pavement driving. Using 4WD on dry pavement, even for short periods, risks increased tire wear and drivetrain strain.
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Improved Fuel Efficiency in 2WD
A significant advantage of the part-time system lies in its ability to improve fuel economy. When operating in 2WD, the front drivetrain components remain disengaged, reducing rotational mass and parasitic losses. This results in better fuel mileage compared to full-time systems that continuously power all four wheels. This fuel efficiency benefit becomes particularly noticeable during highway driving, where consistent speeds and minimal traction demands favor 2WD operation.
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Versatility for Varied Conditions
Despite the limitations on dry pavement, the part-time system offers considerable versatility. It allows the WJ to handle diverse terrains and weather conditions, transitioning seamlessly from fuel-efficient on-road driving to capable off-road performance. This adaptability makes it suitable for drivers who encounter both paved roads and challenging terrains. The ability to switch to 4WD provides a significant advantage in snow, mud, or off-road situations, enhancing safety and traction when needed.
The part-time 4WD system in the WJ presents a balance between fuel efficiency and off-road capability. Recognizing the importance of manual mode selection and the limitations of 4WD on dry pavement ensures optimal performance and drivetrain longevity. This system caters to drivers seeking a versatile vehicle capable of handling both daily commutes and off-road adventures.
6. Transfer Case
The transfer case forms the core of the “select drive” system in the Jeep Grand Cherokee (WJ), acting as the intermediary between the transmission and the differentials. This component determines how power is distributed between the front and rear axles, dictating the vehicle’s drive mode. A comprehensive understanding of the transfer case’s role is fundamental to appreciating the WJ’s capabilities and operational nuances.
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Mode Selection
The transfer case executes the driver’s commands issued through the “select drive” system. Whether shifting into 2WD, 4WD High, or 4WD Low, the transfer case physically alters the power flow. For example, in 2WD, it directs power solely to the rear wheels. Conversely, in 4WD High, it splits the power evenly between both axles. This dynamic power distribution defines the WJ’s adaptability to varying terrains and driving conditions.
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Low-Range Gearing (4WD Low)
A defining feature of the transfer case is its low-range gear ratio. Engaging 4WD Low activates this lower gear set, effectively multiplying engine torque and reducing output speed. This mechanical advantage proves essential for extreme off-road scenarios, such as climbing steep inclines or traversing challenging obstacles. The increased torque allows for controlled wheel rotation at low speeds, maximizing traction and minimizing the risk of wheel slippage.
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Neutral Position
The transfer case also provides a neutral position, essential for flat towing. This setting disengages the drivetrain from the axles, allowing the vehicle to roll freely without engine power. This prevents damage to the transmission and transfer case during towing, highlighting a critical safety feature. Failure to utilize this neutral position during towing can result in significant mechanical damage.
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Maintenance and Durability
Regular maintenance of the transfer case, including fluid changes and inspections, is crucial for ensuring its long-term reliability. Operating under demanding conditions, especially in 4WD Low, subjects the transfer case to significant stress. Proper lubrication and periodic inspections help prevent premature wear and potential failure. Neglecting this essential maintenance can lead to costly repairs and compromise the WJ’s off-road capabilities.
The transfer case represents the operational heart of the “select drive” system in the Jeep Grand Cherokee (WJ). Its ability to precisely control power distribution to the axles, coupled with the low-range gearing and neutral position, enables the WJ to adapt to diverse driving conditions, from paved highways to demanding off-road trails. Understanding its functionality and maintenance requirements is paramount for responsible and effective operation of this versatile vehicle.
Frequently Asked Questions
This section addresses common inquiries regarding the “select drive” system in the Jeep Grand Cherokee (WJ), aiming to clarify its functionality and address potential misconceptions.
Question 1: Can 4WD High be used on dry pavement?
While mechanically possible, using 4WD High on dry pavement is generally discouraged. The lack of wheel slippage on high-traction surfaces can lead to drivetrain binding and increased tire wear. Reserving 4WD High for low-traction situations maximizes drivetrain longevity and fuel efficiency.
Question 2: When should 4WD Low be engaged?
4WD Low is designed for extreme off-road situations requiring maximum torque and low speeds. Steep inclines, deep mud, sand, and rock crawling are ideal scenarios. Engaging 4WD Low should occur at a complete stop or very low speeds to avoid damage to the transfer case.
Question 3: What is the purpose of the “Neutral” position?
The primary purpose of “Neutral” is to facilitate flat towing. It disengages the drivetrain, allowing the vehicle to roll freely without engine power. This prevents damage to the transmission and transfer case during towing. Following the correct procedure for engaging neutral is crucial.
Question 4: How often should the transfer case fluid be changed?
Adhering to the manufacturer’s recommended maintenance schedule is essential. Generally, transfer case fluid changes are advised every 30,000 to 60,000 miles, depending on driving conditions and usage. Regular fluid changes contribute significantly to the transfer case’s longevity.
Question 5: What indicates a problem with the “select drive” system?
Unusual noises, difficulty shifting between modes, or a binding sensation during turns can indicate a problem with the “select drive” system. Prompt inspection by a qualified mechanic is recommended to diagnose and address any potential issues before they escalate.
Question 6: Can the “select drive” system be converted to full-time 4WD?
While aftermarket modifications might offer such conversions, they are generally not recommended. Such alterations can compromise the system’s reliability and potentially void manufacturer warranties. Consulting a Jeep specialist is advisable before considering such modifications.
Understanding these key aspects of the “select drive” system allows for its safe and effective use, enhancing the WJ’s off-road capabilities while maintaining optimal on-road performance. Careful operation and regular maintenance are paramount for ensuring its longevity and reliability.
This concludes the FAQ section. The following section delves further into specific maintenance procedures and troubleshooting tips for the “select drive” system.
Essential Tips for Maintaining the “Select Drive” System
Maintaining the “select drive” system in optimal condition ensures reliable performance and longevity. The following tips provide practical guidance for preserving this crucial component of the Jeep Grand Cherokee (WJ).
Tip 1: Regular Fluid Changes
Adhering to the manufacturer’s recommended fluid change intervals is paramount. Fresh transfer case fluid lubricates internal components, reducing friction and wear. Consult the owner’s manual for specific fluid type and change intervals.
Tip 2: Inspect for Leaks
Regularly inspect the transfer case and surrounding areas for fluid leaks. Leaks can indicate potential issues such as worn seals or damaged components. Addressing leaks promptly prevents further damage and maintains system integrity.
Tip 3: Avoid Extended Use of 4WD on Dry Pavement
Prolonged use of 4WD on dry, high-traction surfaces can cause drivetrain binding and accelerated wear. Restricting 4WD usage to low-traction conditions preserves drivetrain components and optimizes fuel efficiency.
Tip 4: Engage 4WD Low Only When Necessary
4WD Low generates significant torque and should be reserved for extreme off-road situations. Engaging 4WD Low at a complete stop or very low speeds prevents damage to the transfer case.
Tip 5: Shift Carefully Between Modes
Avoid forceful shifting between 2WD and 4WD modes. Smooth and deliberate shifts prevent damage to the transfer case linkage and internal components.
Tip 6: Listen for Unusual Noises
Unusual noises such as grinding, whining, or clicking can signal potential problems within the “select drive” system. Prompt investigation by a qualified mechanic can prevent minor issues from escalating into major repairs.
Tip 7: Address Vibrations Promptly
Vibrations felt through the drivetrain, especially during acceleration or deceleration, may indicate issues with the transfer case or related components. Ignoring vibrations can exacerbate the problem and lead to further damage.
Adhering to these maintenance practices maximizes the lifespan and reliability of the “select drive” system. Proactive maintenance minimizes the risk of costly repairs and ensures consistent performance in various driving conditions.
This concludes the tips section. The next section provides a concise conclusion to this comprehensive overview of the Jeep Grand Cherokee (WJ) “select drive” system.
Understanding the Select Drive Jeep WJ
This exploration of the “select drive” system within the Jeep Grand Cherokee (WJ) has provided a comprehensive overview of its functionality, components, and operational considerations. From the fuel efficiency of 2WD to the enhanced traction of 4WD High and the low-speed power of 4WD Low, the system’s versatility allows the WJ to adapt to diverse driving conditions. The importance of proper mode selection, regular maintenance, and prompt attention to potential issues has been emphasized. Understanding the role of the transfer case as the central component, along with the implications of the part-time 4WD design, equips owners with the knowledge necessary for responsible vehicle operation.
The “select drive” system contributes significantly to the WJ’s legacy as a capable and versatile SUV. Competent operation and diligent maintenance ensure the system’s longevity and reliability, enabling drivers to confidently navigate various terrains and conditions. This knowledge empowers informed decisions regarding vehicle usage and maintenance, ultimately maximizing the WJ’s potential and contributing to a safer and more enjoyable driving experience.
