关于指南者Freedom Drive I系统的技术资料介绍，从克莱斯勒的维修手册里摘录的原文及对应翻译：（翻译由Sk8ter同学完成）
The all-wheel-drive system requires no driver input or control. Under most driving conditions, it is passive and power is transmitted to the front wheels alone. Unlike all-wheel drive systems that rely on pumps or viscous fluids to transfer torque, this system requires no front-to-rear slippage for activation. This allows the system to transfer torque solely in response to accelerator pedal position. If the driver is asking for a lot of power, the system immediately starts clamping the electronically controlled coupling (ECC), transferring a high percentage of power to the rear wheels. This avoids front wheel slippage, as power to propel the car is transmitted through all four tires. This mode of operation is called open-loop operation in that there is no feedback to affect the torque transfer.
全轮驱动系统无需驾驶员进行对其运行进行干涉。在大部分驾驶条件下，它是被动的且动力只输出至前轮。不像其他的全轮驱动系统那样，工作的时候需要依靠泵或者粘性液体来传输扭矩，Freedom-drive系统无需依靠前后轴之间产生的转速差来激活其工作。这就允许该系统仅依靠油门位置来判断输出至前后轴的扭矩比例。如果驾驶员突然大脚油门，则系统就会立即锁定“ECC（电控耦合器）”，把大量的动力传输至后轮。发动机的动力同时传输至四个轮子，进而避免了前轮产生空转。这样的操作模式叫做“开路模式（与闭路模式相对）”，该模式无需路面摩擦力反馈来决定前后轴的输出比例。
A second, closed loop, operating mode uses feedback from the wheel-speed sensors to determine the appropriate torque transfer. When the front wheels slip, the All Wheel Drive (AWD) Control Module tells the ECC to start clamping, sending power to the rear wheels. Attempting the same aggressive launch described above with the front wheels on ice and the rear wheels on dry pavement, the ECC sends even more torque to the rear wheels to minimize slippage and launch the vehicle. Both modes are always active with the closed loop mode layered on top of open loop mode to increase torque to the rear wheels when needed to maintain traction in extreme cases.
第二种模式，即与上面“开路模式”相对的“闭路模式”，则需要车辆轮胎的速度感应器来决定应该适当的扭矩输出比例。当前轮产生空转的时候，全轮驱动控制单元就会将“ECC（电控耦合器）”锁定，将动力传输至后轮。如果在上面提到的例子里，即驾驶员突然大脚油门的情况下，同时前轮在冰面而后轮在干燥炉面，则“ECC（电控耦合器）”则会传输更多的扭矩到后轮，来最大程度的减少前轮产生的空转，从而顺利的开动车子。两种模式状态下都是有效果的，闭路模式基于开路模式来增加输出至后轮的扭矩值，来保证车子在极端条件下的抓地力。

Power to the rear wheels is modulated under the following conditions:
Slipping on ice while backing up will send a lot of power to the rear axle.
Loss of traction while traveling at freeway speeds, for example hydroplaning on a puddle of water, will send very little power to the rear wheels because the controller knows at those speeds a lot of power is not needed at the rear wheels.
前后轮扭矩输出比例的几个决定条件：
在冰面上倒车产生轮胎空转的时候，系统会传输大量动力至后轴。
高速行车时突然失去抓地力的时候，例如在水坑里产生轮胎打滑（即“水上飞机效应”），这个时侯系统就会传输非常少的动力至后轴，因为控制系统知道在那样的条件下，后轮无需大量的动力。
A third condition, which is independent of the others, uses wheel speed differences to determine when the vehicle is turning in a tight circle. This condition, which is indicated by a large discrepancy in side-to-side wheel speeds, causes the electronic control module to reduce torque to the rear wheels to prevent binding in the driveline. The electronic control module is always checking for this condition as well.
第三种条件，也是freedom-drive系统有别于其他四驱系统的是，依靠车辆转急弯时的轮端速度差来决定前后轴扭矩输出值。当左右轮端产生明显的转速差时，电控单元系统就会减少后轮的动力输出以预防动力传输系统产生“较劲”。系统的电控单元会对这种条件进行实时检测。
A fourth condition that is unique to this system is to influence vehicle dynamics. Other systems limit AWD to aiding traction or providing off-road capability. The primary focus is on launching the vehicle or going off road at speeds up to about 25 mph (40 km/hr). Above that speed range, they use it to limit wheel slip for traction. On this system, additional ECM calibration controls torque to the rear wheels for improved handling in the 25-65 mph (40-105 km/hr) range. In this speed range, the system increases torque to the rear wheels during cornering with the throttle open to make the car turn more easily - make the handling more neutral. This is more readily accomplished with an electronically controlled system, than with viscous-coupling or gerotor systems that require some degree of front-to-rear slip to transfer torque to the rear wheels. Above 70 mph (113 km/hr), the control strategy provides minimal torque to the rear wheels under normal driving conditions to aid fuel economy.
第四个条件，也是freedom-drive系统独门绝活，即这个四驱系统可以影响车子的动态操控性。

其他的全轮驱动系统仅限于为车子增加抓地力以及提高越野通过性能，且它们主要的工作重点是保证车子顺利起步，以及在时速低于40公里每小时（25英里每小时）条件下的越野通过性。超过40公里每小时以后，这些系统就利用它来限制车轮空转来保证抓地力（？）。

在Freedom-drive系统上，配备有额外的ECM（电子控制模块）来控制输出至后轮的扭矩，在40-105公里每小时的速度区间内来提高车子的动态操控性能。在这个速度区间内，当车子在油门开启的状态下转弯时，系统可以增加后轮的扭矩输出，从而让车子转弯转的更容易些，减少不必要的转向过度或转向不足。这种电控系统，相较粘液耦合系统或者齿轮油泵系统来说，无需依靠前后轮产生的转速差来决定是否需要传输动力至后轴，从而也更容易完成整个扭矩的输出动作。
在车速超过113公里每小时（70英里每小时）以后，系统就会将输出至后轮的扭矩值降到最小，以提高燃油经济性。
The control module also interfaces with the Electronic Stability Program (ESP) and traction control systems. The interface allows the ESP system to use the ECC to help gain control of the vehicle. For this purpose, torque transmitted to the rear wheels by the ECC can be reduced. This system is not traction control. It only works on situations where front-to-rear traction varies, for instance, front wheels on ice, rear wheels on dry pavement or climbing steep grades. AWD does not aid side-to-side traction. ESP does that through brake intervention on this system.

控制单元也会和ESP（车身稳定控制系统）、TCS（牵引力控制系统）相互配合协调工作。具体说来，就是ESP可以利用ECC的耦合动作来协助控制车身姿态。在这种情况下，依靠ECC系统传输至后轮的扭矩值将会减少。然而这种情况并不是为了控制牵引力（即发动机整体动力输出值不变，只是前后轮动力输出比例发生改变），它仅仅在前后轮抓地力不同，例如前轮在冰上，后轮在干燥炉面上，或者爬陡坡的时候才会工作。全轮驱动系统不会增加左右轮端的牵引力（即不会产生差速锁的效果），而是通过ESP系统用刹车来即对空转的车轮进行刹车动作，防止扭矩流失。

那要看你所指的高档四驱是什么啦。

小指这个四驱能够保证在湿滑路面上平稳驾驶。
人家那是玩儿越野的，基本上就属于上天入地无所不能型的了~哈哈。