The Quadra-Drive system consists of a transfer case with a limited slip coupling inside it that allows changes in driveshaft speed between the front and rear axles to accommodate varying power needs for cornering and changing traction. The differentials, both front and rear, are automatic limited slip side-to-side for the same demands. The need for proper fluid changes and maintenance of this system is important for long life.



SO...This allows the torque to be shifted to any wheel that is slipping automatically without any input from the driver. We shouldn't notice any of this action unless the surface is rough or slippery, like in the rain, mud, or snow. You should hardly ever need low range unless you're pulling extremely heavy loads up a sharp incline at low speeds or descending a very steep hill and need to creep.



There is a drive system called the Quadra-Trac I that doesn't even have a shift lever and remains in 4wd at all times. That system doesn't have a neutral or low range in it. Transfer case neutral is just for towing the vehicle or shifting into low range as in your jeep. Salesmen have told me that system was designed for people that get nervous about what to do with that second shift lever!



You've probably had XJs (Cherokee Sport) before with the NP231 t/case. This t/case gives you 2wd and only has part-time 4wd which locks both axles together with no slippage between them. This is the one that you must not drive on dry pavement in 4wd or risk breaking something. The NP242 in the Grand Cherokees is selectable with 2 different 4wd options, full-time and part-time as well as 2wd.



One thing I'm going to warn you about. It's not a good idea to use cruise control in heavy rain or snow at highway speeds with any automatic 4wd system because the system will "hunt" for traction and give you a very queasy feeling. Personally, I don't like using cruise in ANY vehicle in bad road conditions.