Differential Unit problems of the 2008 Jeep Cherokee

My vehicle has been maintained by the dealership. I have 56k miles on a 2008 Jeep grand Cherokee limited hemi 8cylinder I do not do any off roading I am told today that I need an upper differential housing insulator and pinion seals which are leaking. These products should last longer than 56k in miles and are a considerable cost to the consumer for a 5 year old Jeep. There are several bulletins out about this issue but Jeep did not consider helping me because I was out of my 3 year 36,000 mile warranty which is clearly not enough for defective parts. Please see other complaints for a recall issue. Thank you.

Driving at the posted speed limit on a 4 lane divided highway, the 2008 Jeep grand Cherokee my wife was operating, violently and without warning swerved off the road. My wife described the event as "all the wheels suddenly stopped spinning". The SUV first went off the right shoulder of the road, then skidded across two lanes of traffic and swerved off the left shoulder, nearly rolling over and coming to rest in the median near an embankment. The vehicle was towed to a nearby Jeep dealership where it was subsequently evaluated. The service manager noted that the problem was related to the rear differential. He surmised that the component was assembled "out of spec" and subsequently failed catastrophically. The differential was rebuilt and the vehicle returned. Under the circumstances, my wife will not drive this SUV again.