Hello, My truck drives and shifts fine. while driving i can hit the a/c button and with in a few minutes the transmission is not working. it acts like it is in neutral. pull over to side of road put in park shut off the engine and turn off the a/c, back to normal. Can drive it without any issues until I hit the a/c button, same issue. Any kind of help or information would be greatly appreciated. Thank you

 

Hmmm. I'm trying to remember where those two systems are at all connected. Perhaps there is a short in the wires ?

 

Unhook the AC idle up valve and see if it still does it. Its one of the three little vacuum valves mounted in the engine bay above the passenger side fender. The truck will run without it. It just may idle slower while the compressor clutch is engaged. Should just be able to disconnect the electrical connector on it. Let us know.

 

I will give that a try and let you know what happens. I have taken it to several place to be worked on and they think I'm crazy until they drive it and hit the a/c. No luck on any ideas so far.

 

That sounds like heat buildup, you can try cleaning the condenser in front of the radiator and between the two.