I have a 97 GT and the auto trans is slipping. I need to if the trans from a 2001 crown vic will swap in to my pony and if I need to change any parts

 

I don't believe so...

 

The 4R70W got real tricky around 01 with what will work and what wont. You would be better off getting the proper year trans.

 

It technically will bolt right up, but there are differences in the speed sensors between the two; VSS vs OSS, and I forget which years used which (earlier was OSS I believe). The pcm needs a proper signal from that sensor in order to operate the transmission properly, if it were me I would follow the advice given above and source a transmission from an earlier vehicle or look into having yours rebuilt.

 

Here dude, for $1400 + or - $100 for shipping. you can get a full rebuilt Auto for your ride.

http://www.ebay.com/itm/MPS-HD500-HIGH-PERFORMANCE-4R70W-AUTOMATIC-TRANSMISSION-96-97-FORD-MUSTANG-4-6-/140889287898?hash=item20cda7ecda&vxp=mtr