If switching from a T56 (manual trans) to a 4L60E on your LS vehicle, this harness is what you need to make it work properly. Plugs into the new transmission and the other end is fully terminated and labeled for easy hook-up to your ECM connectors. ECM reprogramming required for proper operation.
This is designed for use on vehicles using the 99 and newer LS1 style PCM in Camaros, Firebirds, and Trucks. It will not work with E40, E38, or E67 controllers.