Hey guys I'm having tranny problems in my 1996 Tahoe and I figured u all could help me with it since it also has a 4l60e..well first time it happened is when I was pulling my atv on my 5x10 trailor and I went to get on the highway stepped into it and it was like I just put into neutral nothing was there until I eased off the gas and u could feel it grab well I was barely able get to 40 and It was not wanting to shift not kool when u have a big rig on ur *** and u can't do anything until I got off the next exit..well the light came on so I had it checked today and it says code po700 transmission control system malfunction...does anybody know what could be wrong? Sorry so long! Thanks

Well I am not sure on a 96 but in the GTO PO700 simply is telling you theres a code stored in the TCM which is separate from the PCM I will research it more and post more

That code in every refrence I have available which is most of them is a Trans Control system Malfucntion. Basically it is saying there is a problem with the transmission controller. However on a 1996 tahoe the controller is intragal to the pcm however it is on a seperate board inside the case. I would say to look at the PCM cases and see if it has split in half at the seem. Very common problem with that pcm in Vans.