Transmission Issue???

Im onto about 10K since my tranny rebuild and latley its been acting up. At first I figured it was just slipping but then I read that it could be a throttle cable?? inside the trans? The symptoms are, if I go WOT from a dead stop it will get to about 4200 rpms it just not upshift for a few seconds the truck will stay at about 40mph until it slams into gear. BUT if Im rolling from 25-30 and stomp it, it drops to first and shifts perfectly fine. 2nd to third just wont up shift if im WOT but if I give it lets say 90% it shifts fine. I was ready to rip it out and get a replacment, whats the deal?

What Kind of transmission is it? I dont believe the throttle has anything to do with the trans but the adjustment of your passing gear cable can affect the way they shift. Have u recently changed the trans fluid? It's possible that a piece of debri has gotten into the valve body. I've had something similar to that happen. I unhooked the passing gear cable, started the truck and then worked the cable back and forth about a dozen times. Whatever had gotten into the valve body came out and it was fine afterward. just a thought.....?

its a 4l60e and I havnt changed the trans fluid since Ive had it done. Yes the passing gear cable is what I ment, What is the process for taking it off and moving it around like you did?

its a 4l60e and I havnt changed the trans fluid since Ive had it done. Yes the passing gear cable is what I ment, What is the process for taking it off and moving it around like you did?

If it is a 4l60e, there is no cable. Shifting is controlled by the PCM based on TPS values, RPM and current speed.

//2000CAYukon