Possible Torque Converter Problem

What is your question?

I took my car to the dealership and they told me I have a bad torque converter that needs to be replaced. I brought it in for a metal on metal sound coming from the rear end. This noise only happens about once a week and only lasts for about 5 minutes. When it is there, it is there at any speed. My trans shifts fine. My car has stalled out twice in the 4 years i owned it, both times while braking. My car only has 68000 miles. Any ideas?