I have a 1998 formula ls1 with an auto transmission. When at WOT I can not manually shift from 1st to 2nd or 2nd to 3rd. If I put it in drive and floor it,it will shift perfectly.I recently burned some gears in the trans and had it rebuilt. I thought rebuilding it might solve this problem but it didn't. Anyone have any ideas on this?

 

well it could be a tuning issue but what do you mean by wont shift ?

 

when I shift it from 1-2 or if I try to shift it 2-3 it hits the rev limiter no matter how early I shift

 

There could be some issue with the overun clutch leakage broken piston seal, sounds like you have a pressure leak when its applied since that the only main difference between OD and manually shifting

 

Thanks I will look in to that.