Automatic Transmission Torque Converter problems of the 2008 Jeep Liberty

2008 Jeep Liberty chatters when backing up slight incline. Problem since new. Still under warranty. Dealer installed torque converter and new rear drive shaft on two different visits. Neither solved issue. Dealer and Chrysler told me that this is ". . . The nature of the beast. " local service rep. Told me that he's driven several with same problem. Chrysler refuses to go any further with solving the issue, basically, telling me to ". . . Live with it. " if, indeed, it is ". . . The nature of the beast. . . ," shouldn't there be a recall to address this? at this point, I'm looking into litigation for breach of contract, as their warranty assures me a flawless product. The consumer stated the vehicle would shudder or jerk while backing up on an incline. The consumer was advised by a chrsyler rep to take the vehicle to a local transmission shop to get a diagnosis only. The repair shop believed the problem was the front u-joint on the rear driveline which was very stiff in one direction, the slip yoke was a little stiff and the hill brake did not release quick enough. The driveline was installed. However, the problem continued. Updated 01/12/11.

A bad grinding sound at 40mph 2008 Jeep Liberty has 800 miles on it had to fix torque converter on it did not fix the problem, service rep. Is test driving it to see what's doing it.