that problem seems to sound like the problem that the older style Taraus had, the car almost wouldn't move while in first. When that happened the transmission had failed and was replaced. But that may not be it, my mother 98 windstar wasn't slipping but was making some funny noises at highway speed, a filter change and new fluid took care of that. I would say change the filter and fluid and see if that makes a difference. Also make sure you have enouhg fluid in the transmission since I beleive the fluid and filter are suppose to be changed around 50k
Son - 1995 Mystique LS Zetec 5-spd --> newest "mod" -> a girlfriend by my side
Father - 1995 Contour SE Duratec 5-spd
Mother - 1999 Contour SE Sport Duratec 5-spd
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