Transmission... Help!!!

Ok, here's the deal. I just bought my 94 Crown Vic recently, drove it home two hundred miles with no problem whatsoever. The tranny fluid was clean and red, no burnt smell or anything like that, it shifted fine except a couple times it couldn't decide when to downshift. I drove it for two weeks, ran like a dream, then one day I shifted it into drive on a slight incline, and it rolled backwards a little bit while in gear. I didn't like it, but I didn't know what to do about it so I decided to watch it, and sure enough, within two days it was having problems with first and second gear. It drove fine at highway speeds, but in town I'd pull up to a stop sign and when I tried to go again the engine would rev uselessly for a couple seconds before it dropped into gear with a sharp jerk. I made it home, and now it sits in my driveway and the only direction it goes is backwards. Put it in a forward gear and it acts just like it's in neutral.
Now I've come up with the theory that it's the switch that gets directions from the computer to tell it which gear to go into. I don't believe it's the transmission itself. I need to know what exactly you call that switch and I also want to know how in the world that car dealer made it work that long. Any help would be appreciated. :banghead: Thanks

It could be the transmission, I'm not sure. Had a similar problem when I used to drive my boss's (sp?) Windstar. It was pure hell when at an incline...

:banghead: :banghead: :banghead:

Today is your lucky day! I had the exact same probelm, you rev the living daylights out of it and it starts to roll, then as soon as it shifts into second you can drive as fast and as far as you like, until you come to a stop. Reverse is perfect. the tranny isn't gone, there is a small valve seal inside the tranny that has popped out of place, and is letting the fluid bypass in first gear. I found out the hard way after I spent the day revving it to get around. what will finally happen is that your overdrive clutch and reverse will weld themselves together. This was good and bad for me,as long as I take the overdrive off, the car is great(only with 3 speeds instead of 4). I have put another 9000 km on the car, the only problem is that ever gear position including neutral is drive, and I have no reverse.