i HAVE A 98 Z28 AND AAT NORMAL DRIVING SPEEDS EVERYTHING WORKS PERFECT. IT SHIFTS PERFECT EVEN WHEN I'M ON IT PRETTY HARD. BUT ONCE I FLOOR IT, IT REVS TO 7000 RPM AND JUMPS OFF THE LIMITER AND STILL WILL NOT SHIFT UNTIL IT GETS DOWN TO ABOUT 3300 RPM. I DID MAIL ORDER TUNING WITH TEXAS SPEED. MAYBE THAT HAD SOMETHING TO DO WITH IT. I PURCHASED HP TUNER AND NEED HLP WITH TRANNY SETTINGS IF ANYONE CAN HELP IN SOUTHERN CA. IT WOULD BE GREATLY APPRECIATED OR IF ANYONE KNOWS WHAT THIS PROBLEM MAY BE. PLEASE HELP. THAK YOU

 

Check your tranny fluid. And also try to ask this question in the pcm section since you have the HP tuner program.

 

4l60e is a piece of ****

 

thanks for the help guys. i am gonna ask in pcm forum. but my fluid is fine. thanks again. and u r right the 4l60e is a piece of ****. ithink i might go with a th-400.

 

I think it is the TSP tune. I have the same deal and so does my buddy on the 3-4 shift, same tunes.. Let me know if you get it figured out.

 

so if the 4l60e sucks wat will be a good tranny?or can u fix wat makes it sucks?and have a problem to i posted it up.