1998 Camaro SS Transmission Issue: Help!

I have a 1998 Camaro SS that recently started to have slippage in the transmission (4L60E). I was about to put 2500miles on it for a road trip so I decided to get the transmission rebuilt at a reputable shop that I have used before. They replaced the 2-4 band during the rebuild. After 5 hours of driving I noticed it was "slipping" when I was in OD shifting to third. During gentle acceleration it was fine. However, when I was in OD and gave it moderate throttle to pass, it would just rev right up without an increase in speed. The car is now 2500 miles away from that shop so I can't bring it back to them.

Calling around to some local shops, I have been told to look at the MAF sensor as that supposedly directs line pressure to and from the transmission and as a result my transmission could be burnt again because of this faulty sensor.

One shop test drove the car and indicated that the car was "neutralizing" and not in fact slipping. The mechanic said that it was most likely from a sticky component in the valve body.

I am no transmission expert and now have had numerous diagnostics done with varying results. Before I take it in to a shop, I would like to have a better idea as to what might be the issue. What I have written is just forwarding on what the mechanics have passed on to me. I would appreciate any information or suggestions as to what I can check or test!

Are any diagnostic trouble codes (DTC's) being set? I agree that the PCM looks at engine sensor data to control the transmission, however, it is likely that you would be having other issues as well if the MAF was not reading properly.

No codes are being set from this and as far as I can tell I am not having any other issues

I have not heard of a car "neutralizing" but I suppose anything is possible. You can unplug the MAF and force the PCM into speed density fuel calculations. That will set a DTC that can be cleared after the fact. A scanner that can see live data may help you diagnose the problem.