This problem is actually happening in my 1997 chevy silverado. Im thinking it has a 4l60e in it but it may be the 80e I know its one of the two. Anyways the truck only has 23k miles on it. Out of nowwhere a week ago the tranny started acting funny like it has a stall converter in it.. From a stop the tranny will slip to about 1200 rpms maybe a little more and in between shifts it will slip and let the rpms rise a couple of hundred rpms then shift slowly. I also barely have reverse. The weird thing about it is if i disconnect my battery for a few minutes and reconnect it the transmission will drive almost normally for about 5 minutes then start acting up again and it worsens as I drive it more. Any suggestions on what could be causing this? I really didnt want to spend a grand to rebuild the tranny after i just did H/c on my camaro