Do you know how to find out? That will be key to making it happen.
Sorry for being so obvious. Point the search engine of you choice at
https://www.google.com/search?q=Control+mechanism+for+the+4R70W+transmiss ion
There you will find an article at Autospeed that might be a good start.
http://www.autospeed.com/cms/article...art-One&A=2672