700R4 that only mildly backs up at 1200 rpm

[Gilmore]

Well wanted to post an update. TCI replaced the transmission and I installed the new one and it works great. Cost me a little bit of $ to jump through the hoops but at the end of the day it all worked out.

 

[Matt69olds]

Bummer. We will never know what the real problem was.

At least it’s fixed.

 

[Gilmore]

They said they suspected reverse clutch out of tolerance.

 

[GXPWeasel]

Glad to hear you got this figured out Gilmore.
I was going through a very similar situation a little less than a year ago. I got super frustrated as well, and had some great advice from some of the same people you did in this thread. Unfortunately I didn't figure out what my real issue is either, and just had to source a different transmission to fix my issue. I was dealing with a TH350.