I have a 1994 Chevy Silverado with a lq4 swapped attached to a 4l60e. And I recently got the tranny rebuilt due to it not shifting under power. Every time I would step on the gas it will accurate until it needed to shift and it would hit the rev limiter? The transmission guy said it was something in the computer? I would like to know who else has this problem? And how did they fix it? Thanks

 

Since the computer completely controls the shifting "the transmission guy" is correct.
You need to find a local tuner or consider a mail order tune. Check the "PCM Diagnostics and Tuning" section for references and excellent sponsors.