Thread: Rebuilt 4T60E,No shift from 1st

I recently rebuilt my 4t60e transmission,since this was my 1st attempt at such an intense project I used the GM service manual along with the junior shift kit instructions,triple checked everything (I thought),and replaced worn out hard parts. Reverse and 1st are normal and pull great but when it's time for 2nd to engage the trans will neutral until speed drops low enough for 1st to take over again. I have pulled trans and checked valve body and accumulator servo pistons,performed air test on clutch packs and everything seems fine. I am getting 78 psi @ idle,74 in R and N,65 for D,3 and 2,and 1st shows 95 psi.
Anyone have an idea where I screwed things up?

Thanks Bill,I double checked that all of the balls were installed correctly when I re-installed the valve body.
I'm wondering if maybe the seal lip on the 1-2 servo is backwards,or if that would even cause a no shift situation.

I installed the wrong valve body plate gasket in a 4t65e once and only has 2nd and 3rd gear. Are you dead sure you have the right valve body gaskets in there?

I held the spacer plate to a light with the gasket between the light and plate,and could see through all holes,did this for both gaskets.