Bought this Windstar back in 2000 and have driven about 167000 miles with it. Only once did we have a tranny replaced, but I don't remember the mileage. Also had an incident when it refused to shift coming back from a ski trip in WV. Nursed it back, to find that it was a faulty computer chip. Have taken numerous trips to MI (about 1000 mile each way) and has always been solid. The only real issue with my van is that, in the summer it "bings" at you when the driver side door is open and continues to "bing" until you reach 15 mph. The whole time the interior lights will stay on, and the door ajar light stays on. Have had this problem twice. Aparently it's a harness in the steering colum.
3.8L has plenty of power, 2nd row seats lean back, radio controls in the 2nd row. Sound system is nice. Very strong (had a Datsun truck total itself on the back bumper)
Please find a way to fix the tranny problems. Improve the steering colum to stop that "Binging" in the summer. It eats gas (in the city is the worst) about 14-16 mpg (highway's not bad 18- 22)