Automatic Transmission Torque Converter problems of the 1997 Mercury Grand Marquis

Several months ago, I reported a shudder or vibration in the transmission at speeds over 25 mph. I had been told that either the torque converter or 85% of the time the transmission fluid was the problem. A new mercon 5 fluid was being used to eliminate the shudder or vibration. I took the vehicle in today to Ford, who is now reporting the clutch to be going out. I find this very unusual at 48,000 miles with the previous diagnosis given. It sounds like there was a manufacturing defect with the transmissions or related parts for this vehicle. Also both electronic windows on the driver-side have gone out. . . Regulator parts broken. Help!.