I just got the old 700r tranny out of my 86 Z. Just have a quick question before I put the new one in. There is a four prong (Three Wire) Harness on the side of the tranny. Can someone please tell me what this is. Is it a necessity? Thanks!

 

Yes, It is your "TCC lock-up" harness connector. And yes it's important if you don't wish to fry the clutch in the torque convertor!..

 

You had best make sure it is on. It is important for the TCC to do it's lockup

 

What does the "TCC Lockup" do exactly. I don't know a whole lot about transmissions. I can pull them out and put them in, but that's about it. Thanks!