Online research indicates maybe Torque Converter problem

Thanks, I will check the hose you mentioned later. The leaking area seems at driver side by inside of left front wheel.

I found someone has the same issues with Windstar due to torque converter seal problem. See below link. I am not sure where the torque converter seal located.

http://answers.edmunds.com/question-Ford-Windstar-leaking-transmission-fluid-hot-fine-cool-What-problem-18487.aspx

If ATF cooler hose has leak, is it easier to replace the hose?　

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