Windshield Wiper/washer problems of the 2006 Ford Taurus

Since I bought this car the windshield wipers have been a problem in very hard rains or heavy snowstorms. They drivers side windshield wiper would catch onto the other one and get snagged. I would have to pull off to the side of the road and untangle them and sometimes drive real slow bending over to look out of the passengers side window. This would happen off and on during hard rains or heavy snowstorms. This year was the worst. In January or February when we had a heavy snowstorm the driver side windshield wiper would stop in the middle of the cycle and sit right in the center of the windshield. I once again had to drive in peril. This April (29th), we had another heavy snowstorm and the drivers side wiper froze again in the middle of the cycle, then it would slam all the way over onto the drivers side view mirror and get stuck there. I drove to the Ford dealer and they tightened some screw on my wiper and said it was fixed. The same thing happened the next week (March 4th), in a heavy rain. I had to pull off the side of the road again and un-snag the wiper from the side-view mirror. Every time this happened I was in real peril of having an accident. I couldn't see the road and was just lucky that I did not have an accident each time the wipers stopped working properly. I once again went directly to my Ford dealer and they diagnosed the problem as a stripped window wiper transmission. They said the problem was not covered in my extended warranty. I was shocked since I was told that my extended warranty covered everything on the car. I had to pay $89. 50 for a diagnostic then $241. 98 for parts and labor. I researched problems with 2006 Ford Taurus sedans and found that the windshield wiper motor had a recall. I let my Ford dealer know this and told me that it was not the transmission that was bad not the motor. It seems that window wiper design is faulty whether its the motor or transmission.