I am the caretaker of my late father's 2WD Grand Cherokee. Jeep towed to repair shop where it was diagnosed as having dirty pan, so transmission fluid and filter was changed after the pan was cleaned. Got used TCM and now the transmission will shift though the gears. Replaced transmission, Jeep now shifts through all gears." I'm trying to keep my father's Jeep alive; it was his wish for his grandchildren not to drive air-cooled VWs.