Ok 1st I want to start of by saying that I don't know anything about transmission and am only going by what I read and what others tell me. When I called CK and Jakes to inquire about the 200R4 which they both sell they both told me not to bother with it and do the 4l80 which was about the same price. Again I'm not sure why they would try and push me toward the 4l80 over the 200R4? I would rather run the 200 simply b/c of the size comparison between the two.