LS1TL

To start the original transmission lost 3rd and 4th and when it went i saw this as an opportunity to add a new stall converter. After purchasing a new transmission from a shop and an fti3200 stall i put the new trans in. I made sure to slide torque converter all the way down into the new trans when installing. When all finished car immediately lost 3rd and 4th gear due to frying the clutches and im just trying to figure out where i went wrong. I read that spacing between the stall and flex plate can be an issue. Stock flexplate was used when all put back together. Any help?

Crf450r420

iTrader: (1)

What's are the common part between the two transmissions? I would start looking at controller or harness if they are the same and both trans had the same issue. Might not be that it's just where I'd start looking.

Docrocket1967

iTrader: (1)

Did you flush your transmission cooler really well and get all the old crap that was floating around out of it and the transmission lines? If it was an issue with you sliding the torque converter on it would have broke the pump gears and you wouldnt have had movement to begin with. How far did you make it before the 3/4 clutches burned up?