Vehicle Shudder problems of the 1997 Plymouth Grand Voyager

I was driving my ply. Grand voyager se home on wed July 18th at appx 6 pm. I stopped at a light ( I was the first car at the intersection ) and when I took my foot off the brake and pressed on the accelerator, the car made an awful grinding noise. The person behind me assumed that I was moving and came within inches of crashing into me. I stopped the car and turned it off. As I stepped out (into traffic) I did not see any debris or leakage underneath. I tried putting the car into neutral and the car would not move. I had to call the police and aaa to tow me to the dealer. I was told that I needed a new transmission. I have always kept up with my repairs and had no prior history of slippage. I was told that a pin became loose and that the gears simply fell out of place. I was told that this could have happened while driving! this scared me due to the fact that I have a family and my life was in jeapordy while driving what I thought was a safe family vehicle. I could understand if I had prior warning signs of the transmission slipping, but for something like this to happen without any warning is alarming. I hope that this is not a common issue with the Plymouth Grand Voyager. I have owned 5 cars in my lifetime. They have all lasted well into the 100,000 mile range without any major problems due to my diligent maitainance. I feel that this is a serious issue in workmanship that can cause a potential catastrophic end to a driver or a family(ies). I hope that this issue be looked into further, because I feel that this is not an isolated case. Thank you, javier rabelo.