Four-Wheel-Drive Systems

Quadra-Trac I

For Jeep Grand Cherokee customers who want the assurance of full-time four-wheel drive without any switches or levers to pull, Quadra-Trac I is the right system. The system provides for smooth operation of the vehicle over a variety of road surface conditions.

The NV140 transfer case splits torque 48/52 percent (front/rear) for nearly even distribution of engine power. The single-speed transfer case has been designed to rigorous Jeep durability standards while offering smooth and quiet operation. The use of the Brake Traction Control System (BTCS) with the NV140 transfer case makes the 4x4 system extremely competent in most situations.

Quadra-Trac II

The Quadra-Trac II 4x4 system for Jeep Grand Cherokee gives the customer the benefit of the NV245 two-speed active transfer case and BTCS. Quadra Trac II is standard on 4.7-liter V-8 engine and is offered as a new option for 2006 on the 3.7-liter V-6 engine (late availability).

The transfer case is the same one used in the Quadra-Drive II system. It takes input from a variety of sensors to determine tire slip at the earliest possible moment and takes corrective action. The system also uses Throttle Anticipate - sensing quick movement in throttle from a stop - and takes steps to maximize traction before tire slippage even occurs.

Torque is transferred to the individual wheels as needed by the BTCS to maintain traction in changing road conditions. When the system senses tire slip, it modulates brake pressure to the slipping wheel, which directs torque to the tires with the best traction.

Quadra-Trac II features an electronic shift mechanism for ease-of-use. The transfer case offers a low range for off-road situations and includes a neutral position for trouble-free towing behind another vehicle.

Quadra-Drive II

The Quadra-Drive II Jeep 4x4 system offers customers the ultimate in off-road capability. It combines the NV245 full-time transfer case with Electronic Limited Slip Differentials (ELSD) for best-in-class tractive performance. The system instantly detects tire slip and smoothly distributes engine torque to the tires with traction. In some cases, the vehicle will even anticipate low traction and adjust to proactively limit or eliminate slip.

The heart of the system is the NV245 active transfer case. This transfer case includes a center differential coupled with an electronically controlled clutch pack, varying it from a completely open state to completely locked and infinite possibilities in between. The 4-Low gear ratio is 2.72:1.

A key component in the Quadra-Drive II system is the ELSD - an industry-first application front/rear/center - and the new benchmark for automatic traction differentials. The ELSD uses electronically controlled clutch packs to automatically and instantly vary from slip to lock at each axle. This maximizes traction when needed without any of the on-road drawbacks normally associated with such a robust 4x4 system.

All components of the system work together, continually monitoring needs, to provide smooth and automatic application of the components for best-in-class tractive performance while improving the day-to-day on-road driving experience. For example, the ELSD releases the clutch packs in the front axle during turns to allow differentiation and prevent crow hop.