I'm installing a Transgo kit in my 4l60 from a 2004 GTO.

It's not been too bad so far but I'm totally lost on the step where you upgrade the iso-conv valve. I removed the original, plastic one. It says to push the new valve in and out 20 times until it falls in. I did that and it seems to be fine.

The new valve is longer than the original valve and uses a larger spring. I've tried every which way. Even when I drop the new valve in without the spring, there isn't enough room to put the round piston and clip back in.

Any tips or ideas on what I'm doing wrong?

 

Sounds like you did not remove all the pieces from the original line up. In the factory line up there are two valves and one spring. In your new set up you only use the new supplied valve and the supplied blue spring.

Edit where is this plastic piece? Pictures?

 

Thanks Vince, you were right. There was another piece wedged in the very top that I couldn't see. After taking it out, it all went into place.

 

Your welcome. Vince