Several of us have had this problem and the only thing that solved it for me was replacing the pcm. I tried a transmission shop for the symptoms and after wasting time and money took it to the dealer. A new pcm and flashing it to the jeep was what finally solved the issue.....very pricey....also that tranny the 42rle requires an auxiliary cooler for it to behave and long life. There are threads on here which helped me figure it out. Search pcm or 42rle. Hope this helps.