Originally Posted by beertracker
In case this helps some one else here is a Transgo FAQ I found. TransGo
Since my TH350 is used and has wear does it make sense to add a shift kit or re-programming kit? Should these kits only be added to a fresh re-built trans? I ask because I know of one person who added a kit to his TH350 and the trans went out after that. I don't know what kit he installed or the condition of his TH350 before the install.
If the trans is in good working order it won't hurt it. I've put this kit in several good operating used transmissions without any problems.